AP BIO MIDTERM REVIEW

Pregunta 1 de 199

1

Darwinʹs mechanism of natural selection required long time spans in order to modify species. From whom did
Darwin get the concept of Earthʹs ancient age?

Selecciona una de las siguientes respuestas posibles:

Georges Cuvier
Charles Lyell
Alfred Wallace
Thomas Malthus
John Henslow

Explicación

Pregunta 2 de 199

1

Charles Darwin was the first person to propose

Selecciona una de las siguientes respuestas posibles:

that evolution occurs.
a mechanism for how evolution occurs.
that the Earth is older than a few thousand years.
a mechanism for evolution that was supported by evidence.
a way to use artificial selection as a means of domesticating plants and animals.

Explicación

Pregunta 3 de 199

1

Which of these conditions should completely prevent the occurrence of natural selection in a population over
time?

Selecciona una de las siguientes respuestas posibles:

All variation between individuals is due only to environmental factors.
The environment is changing at a relatively slow rate.
The population size is large.
The population lives in a habitat where there are no competing species present.

Explicación

Pregunta 4 de 199

1

Which of the following represents an idea that Darwin learned from the writings of Thomas Malthus?

Selecciona una de las siguientes respuestas posibles:

All species are fixed in the form in which they are created.
Populations tend to increase at a faster rate than their food supply normally allows.
Earth changed over the years through a series of catastrophic upheavals.
The environment is responsible for natural selection.
Earth is more than 10,000 years old.

Explicación

Pregunta 5 de 199

1

Given a population that contains genetic variation, what is the correct sequence of the following events, under
the influence of natural selection?
1. Well-adapted individuals leave more offspring than do poorly adapted individuals.
2. A change occurs in the environment.
3. Genetic frequencies within the population change.
4. Poorly adapted individuals have decreased survivorship.

Selecciona una de las siguientes respuestas posibles:

2 → 4 → 1 → 3
4 → 2 → 1 → 3
4 → 1 → 2 → 3
4 → 2 → 3 → 1
2 → 4 → 3 → 1

Explicación

Pregunta 6 de 199

1

To observe natural selectionʹs effects on a population, which of these must be true?

Selecciona una de las siguientes respuestas posibles:

One must observe more than one generation of the population.
The population must contain genetic variation.
Members of the population must increase or decrease the use of some portion of their anatomy.
A and C only
A and B only

Explicación

Pregunta 7 de 199

1

During drought years on the Galapagos, small, easily eaten seeds become rare, leaving mostly large,
hard-cased seeds that only birds with large beaks can eat. If a drought persists for several years, what should
one expect to result from natural selection?

Selecciona una de las siguientes respuestas posibles:

Small birds gaining larger beaks by exercising their mouth parts.
Small birds mutating their beak genes with the result that later-generation offspring have larger beaks.
Small birds anticipating the long drought and eating more to gain weight and, consequently, growing
larger beaks.
More small-beaked birds dying than larger-beaked birds. The offspring produced in subsequent
generations have a higher percentage of birds with large beaks.
Larger birds eating less so smaller birds can survive

Explicación

Pregunta 8 de 199

1

Which of the following must exist in a population before natural selection can act upon that population?

Selecciona una de las siguientes respuestas posibles:

Genetic variation among individuals
Variation among individuals caused by environmental factors
Sexual reproduction
B and C only
A, B, and C

Explicación

Pregunta 9 de 199

1

How many separate species, both extant and extinct, are depicted in this tree?

Selecciona una de las siguientes respuestas posibles:

2
3
4
5
6

Explicación

Pregunta 10 de 199

1

Which of the five common ancestors, labeled V—Z, has given rise to the greatest number of species, both extant
and extinct?

Selecciona una de las siguientes respuestas posibles:

V
W
X
Y
Z

Explicación

Pregunta 11 de 199

1

Evolutionary trees such as this are properly understood by scientists to be

Selecciona una de las siguientes respuestas posibles:

theories.
hypotheses.
laws.
dogmas.
facts.

Explicación

Pregunta 12 de 199

1

Which statement best describes the evolution of pesticide resistance in a population of insects?

Selecciona una de las siguientes respuestas posibles:

Individual members of the population slowly adapt to the presence of the chemical by striving to meet
the new challenge.
All insects exposed to the insecticide begin to use a formerly silent gene to make a new enzyme that
breaks down the insecticide molecules.
Insects observe the behavior of other insects that survive pesticide application, and adjust their own
behaviors to copy those of the survivors.
Offspring of insects that are genetically resistant to the pesticide become more abundant as the
susceptible insects die off.

Explicación

Pregunta 13 de 199

1

Some members of a photosynthetic plant species are genetically resistant to an herbicide, while other members
of the same species are not resistant to the herbicide. Which combination of events should cause the most
effective replacement of the non-herbicide-resistant strain of plants by the resistant strain?
1. The presence of the herbicide in the environment
2. The absence of the herbicide from the environment
3. The maintenance of the proper conditions for one generation
4. The maintenance of the proper conditions for many generations

Selecciona una de las siguientes respuestas posibles:

1 and 3
1 and 4
2 and 3
2 and 4

Explicación

Pregunta 14 de 199

1

Of the following anatomical structures, which is homologous to the wing of a bird?

Selecciona una de las siguientes respuestas posibles:

Dorsal fin of a shark
Hindlimb of a kangaroo
Wing of a butterfly
Tail fin of a flying fish
Flipper of a cetacean

Explicación

Pregunta 15 de 199

1

Structures as different as human arms, bat wings, and dolphin flippers contain many of the same bones, these
bones having developed from very similar embryonic tissues. How do biologists interpret these similarities?

Selecciona una de las siguientes respuestas posibles:

By identifying the bones as being homologous
By the principle of convergent evolution
By proposing that humans, bats, and dolphins share a common ancestor
A and C only
A, B, and C

Explicación

Pregunta 16 de 199

1

Which of the following pieces of evidence most strongly supports the common origin of all life on Earth?

Selecciona una de las siguientes respuestas posibles:

All organisms require energy.
All organisms use essentially the same genetic code.
All organisms reproduce.
All organisms show heritable variation.
All organisms have undergone evolution.

Explicación

Pregunta 17 de 199

1

Which of the following statements most detracts from the claim that the human appendix is a completely
vestigial organ?

Selecciona una de las siguientes respuestas posibles:

The appendix can be surgically removed with no immediate ill effects.
The appendix might have been larger in fossil hominids.
The appendix has a substantial amount of defensive lymphatic tissue
Individuals with a larger-than-average appendix leave fewer offspring than those with a
below-average-sized appendix.
In a million years, the human species might completely lack an appendix.

Explicación

Pregunta 18 de 199

1

Ichthyosaurs were aquatic dinosaurs. Fossils show us that they had dorsal fins and tails, as do fish, even
though their closest relatives were terrestrial reptiles that had neither dorsal fins nor aquatic tails. The dorsal
fins and tails of ichthyosaurs and fish are

Selecciona una de las siguientes respuestas posibles:

homologous.
examples of convergent evolution.
adaptations to a common environment.
A and C only
B and C only

Explicación

Pregunta 19 de 199

1

Monkeys of South and Central America have prehensile tails, meaning that their tails can be used to grasp
objects. The tails of African and Asian monkeys are not prehensile. Which discipline is most likely to provide
an evolutionary explanation for how this difference in tails came about?

Selecciona una de las siguientes respuestas posibles:

Aerodynamics
Biogeography
Physiology
Biochemistry
Botany

Explicación

Pregunta 20 de 199

1

Heterozygote advantage should be most closely linked to which of the following?

Selecciona una de las siguientes respuestas posibles:

sexual selection
stabilizing selection
random selection
directional selection
disruptive selection

Explicación

Pregunta 21 de 199

1

In a single molecule of water, two hydrogen atoms are bonded to a single oxygen atom by

Selecciona una de las siguientes respuestas posibles:

hydrogen bonds.
nonpolar covalent bonds.
polar covalent bonds.
ionic bonds.
van der Waals interactions.

Explicación

Pregunta 22 de 199

1

An example of a hydrogen bond is the bond between

Selecciona una de las siguientes respuestas posibles:

C and H in methane (CH4).
the H of one water molecule and the O of another water molecule.
Na+and Cl- in salt.
the two hydrogen atoms in a molecule of hydrogen gas (H2).
Mg+and Cl- in MgCl2.

Explicación

Pregunta 23 de 199

1

What gives rise to the cohesiveness of water molecules?

Selecciona una de las siguientes respuestas posibles:

hydrophobic interactions
nonpolar covalent bonds
ionic bonds
hydrogen bonds
both A and C

Explicación

Pregunta 24 de 199

1

Which of the following takes place as an ice cube cools a drink?

Selecciona una de las siguientes respuestas posibles:

Molecular collisions in the drink increase.
Kinetic energy in the drink decreases.
A calorie of heat energy is transferred from the ice to the water of the drink.
The specific heat of the water in the drink decreases.
Evaporation of the water in the drink increases.

Explicación

Pregunta 25 de 199

1

The nutritional information on a cereal box shows that one serving of a dry cereal has 200 kilocalories. If one
were to burn one serving of the cereal, the amount of heat given off would be sufficient to raise the temperature
of 20 kg of water how many degrees Celsius?

Selecciona una de las siguientes respuestas posibles:

0.2°C
1.0°C
2.0°C
10.0°C
20.0°C

Explicación

Pregunta 26 de 199

1

Which type of bond must be broken for water to vaporize?

Selecciona una de las siguientes respuestas posibles:

ionic bonds
nonpolar covalent bonds
polar covalent bonds
hydrogen bonds
covalent bonds

Explicación

Pregunta 27 de 199

1

Hydrophobic substances such as vegetable oil are

Selecciona una de las siguientes respuestas posibles:

nonpolar substances that repel water molecules.
nonpolar substances that have an attraction for water molecules.
polar substances that repel water molecules.
polar substances that have an affinity for water.
charged molecules that hydrogen-bond with water molecules.

Explicación

Pregunta 28 de 199

1

One mole (mol) of a substance is

Selecciona una de las siguientes respuestas posibles:

6.02 × 10^23 molecules of the substance.
1 g of the substance dissolved in 1 L of solution.
the largest amount of the substance that can be dissolved in 1 L of solution.
the molecular mass of the substance expressed in grams.
A and D only

Explicación

Pregunta 29 de 199

1

When an ionic compound such as sodium chloride (NaCl) is placed in water the component atoms of the NaCl
crystal dissociate into individual sodium ions (Na+) and chloride ions (Cl-). In contrast, the atoms of covalently
bonded molecules (e.g., glucose, sucrose, glycerol) do not generally dissociate when placed in aqueous
solution. Which of the following solutions would be expected to contain the greatest number of particles
(molecules or ions)?

Selecciona una de las siguientes respuestas posibles:

1 L of 0.5 M NaCl
1 L of 0.5 M glucose
1 L of 1.0 M NaCl
1 L of 1.0 M glucose
C and D will contain equal numbers of particles.

Explicación

Pregunta 30 de 199

1

The molecular mass of glucose (C6H12O6) is 180 g. Which of the following procedures should you carry out to
make a 0.5 M solution of glucose?

Selecciona una de las siguientes respuestas posibles:

Dissolve 0.5 g of glucose in a small volume of water, and then add more water until the total volume of
solution is 1 L.
Dissolve 90 g of glucose in a small volume of water, and then add more water until the total volume of
the solution is 1 L.
Dissolve 180 g of glucose in a small volume of water, and then add more water until the total volume of
the solution is 1 L.
Dissolve 0.5 g of glucose in 1 L of water.
Dissolve 180 g of glucose in 1 L of water.

Explicación

Pregunta 31 de 199

1

You have a freshly-prepared 0.1M solution of glucose in water. Each liter of this solution contains how many
glucose molecules?

Selecciona una de las siguientes respuestas posibles:

6.02 × 10^23
3.01 × 10^23
6.02 × 10^24
12.04 × 10^23
6.02 × 10^22

Explicación

Pregunta 32 de 199

1

You have a freshly-prepared 1M solution of glucose in water. You carefully pour out a 100 mL sample of that
solution. How many glucose molecules are included in that 100 mL sample?

Selecciona una de las siguientes respuestas posibles:

6.02 × 10^23
3.01 × 10^23
6.02 × 10^24
12.04 × 10^23
6.02 × 10^22

Explicación

Pregunta 33 de 199

1

Which of the following ionizes completely in solution and is considered to be a strong base (alkali)?

Selecciona una de las siguientes respuestas posibles:

NaCl
HCl
NH3
H2CO3
NaOH

Explicación

Pregunta 34 de 199

1

What is the pH of a solution with a hydroxyl ion [OH-] concentration of 10-12 M?

Selecciona una de las siguientes respuestas posibles:

pH 4
pH 2
pH 6
pH 8
pH 10

Explicación

Pregunta 35 de 199

1

Organic chemistry is a science based on the study of

Selecciona una de las siguientes respuestas posibles:

functional groups.
vital forces interacting with matter.
carbon compounds.
water and its interaction with other kinds of molecules.
inorganic compounds.

Explicación

Pregunta 36 de 199

1

The experimental approach taken in current biological investigations presumes that

Selecciona una de las siguientes respuestas posibles:

simple organic compounds can be synthesized in the laboratory from inorganic precursors, but complex organic compounds like carbohydrates and proteins can only be synthesized by living organisms.
a life force ultimately controls the activities of living organisms and this life force cannot be studied by physical or chemical methods.
although a life force, or vitalism, exists in living organisms, this life force cannot be studied by physical or chemical methods.
living organisms are composed of the same elements present in nonliving things, plus a few special trace elements found only in living organisms or their products.
living organisms can be understood in terms of the same physical and chemical laws that can be used to explain all natural phenomena.

Explicación

Pregunta 37 de 199

1

Which of the following people used this apparatus to study the formation of organic compounds?

Selecciona una de las siguientes respuestas posibles:

Stanley Miller
Jakob Berzelius
Friedrich Wohler
Hermann Kolbe
August Kekulé

Explicación

Pregunta 38 de 199

1

Which of the following people synthesized an organic compound, acetic acid, from inorganic substances that had been prepared directly from pure elements?

Selecciona una de las siguientes respuestas posibles:

Stanley Miller
Jakob Berzelius
Friedrich Wohler
Hermann Kolbe
August Kekulé

Explicación

Pregunta 39 de 199

1

How many electron pairs does carbon share in order to complete its valence shell?

Selecciona una de las siguientes respuestas posibles:

1
2
3
4
8

Explicación

Pregunta 40 de 199

1

The two molecules shown in the figure above are best described as

Selecciona una de las siguientes respuestas posibles:

optical isomers.
enantiomers.
structural isomers.
cis-trans isomers.
chain length isomers.

Explicación

Pregunta 41 de 199

1

The two molecules shown in the figure above are best described as

Selecciona una de las siguientes respuestas posibles:

enantiomers.
radioactive isotopes.
structural isomers.
nonisotopic isomers
geometric isomers

Explicación

Pregunta 42 de 199

1

Which of the following statements best describes the carbon atoms present in all organic molecules?

Selecciona una de las siguientes respuestas posibles:

They were incorporated into organic molecules by plants.
They were processed into sugars through photosynthesis.
They are ultimately derived from carbon dioxide
Only A and C are correct.
A, B, and C are correct.

Explicación

Pregunta 43 de 199

1

All of the following are part of a prokaryotic cell except:

Selecciona una de las siguientes respuestas posibles:

DNA.
a cell wall
a plasma membrane.
ribosomes.
an endoplasmic reticulum.

Explicación

Pregunta 44 de 199

1

Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules?

Selecciona una de las siguientes respuestas posibles:

lipids
glycogen
proteins
cellulose
nucleic acids

Explicación

Pregunta 45 de 199

1

Which type of organelle or structure is primarily involved in the synthesis of oils, phospholipids, and steroids?

Selecciona una de las siguientes respuestas posibles:

ribosome
lysosome
smooth endoplasmic reticulum
mitochondrion
contractile vacuole

Explicación

Pregunta 46 de 199

1

The fact that the outer membrane of the nuclear envelope has bound ribosomes allows one to most reliably conclude that

Selecciona una de las siguientes respuestas posibles:

at least some of the proteins that function in the nuclear envelope are made by the ribosomes on the nuclear envelope
the nuclear envelope is not part of the endomembrane system
the nuclear envelope is physically separated from the endoplasmic reticulum.
small vesicles from the Golgi fuse with the nuclear envelope
nuclear pore complexes contain proteins

Explicación

Pregunta 47 de 199

1

Tay-Sachs disease is a human genetic abnormality that results in cells accumulating and becoming clogged with very large and complex lipids. Which cellular organelle must be involved in this condition?

Selecciona una de las siguientes respuestas posibles:

the endoplasmic reticulum
the Golgi apparatus
the lysosome
mitochondria
membrane-bound ribosomes

Explicación

Pregunta 48 de 199

1

Which of the following produces and modifies polysaccharides that will be secreted?

Selecciona una de las siguientes respuestas posibles:

lysosome
vacuole
mitochondrion
Golgi apparatus
peroxisome

Explicación

Pregunta 49 de 199

1

Which of the following contains hydrolytic enzymes?

Selecciona una de las siguientes respuestas posibles:

lysosome
vacuole
mitochondrion
Golgi apparatus
peroxisome

Explicación

Pregunta 50 de 199

1

Which organelle often takes up much of the volume of a plant cell?

Selecciona una de las siguientes respuestas posibles:

lysosome
vacuole
mitochondrion
Golgi apparatus
peroxisome

Explicación

Pregunta 51 de 199

1

Which plant cell organelle contains its own DNA and ribosomes?

Selecciona una de las siguientes respuestas posibles:

glyoxysome
vacuole
mitochondrion
Golgi apparatus
peroxisome

Explicación

Pregunta 52 de 199

1

Which animal cell organelle contains enzymes that transfer hydrogen from various substrates to oxygen?

Selecciona una de las siguientes respuestas posibles:

lysosome
vacuole
mitochondrion
Golgi apparatus
peroxisome

Explicación

Pregunta 53 de 199

1

The chemical reactions involved in respiration are virtually identical between prokaryotic and eukaryotic cells. In eukaryotic cells, ATP is synthesized primarily on the inner membrane of the mitochondria. In light of the endosymbiont theory for the evolutionary origin of mitochondria, where is most ATP synthesis likely to occur in prokaryotic cells?

Selecciona una de las siguientes respuestas posibles:

in the cytoplasm
on the inner mitochondrial membrane
on the endoplasmic reticulum
on the inner plasma membrane
on the inner nuclear envelope

Explicación

Pregunta 54 de 199

1

Which of the following are capable of converting light energy to chemical energy?

Selecciona una de las siguientes respuestas posibles:

chloroplasts
mitochondria
leucoplasts
peroxisomes
Golgi bodies

Explicación

Pregunta 55 de 199

1

A cell has the following molecules and structures: enzymes, DNA, ribosomes, plasma membrane, and
mitochondria. It could be a cell from

Selecciona una de las siguientes respuestas posibles:

a bacterium.
an animal, but not a plant.
a plant, but not an animal.
a plant or an animal.
any kind of organism.

Explicación

Pregunta 56 de 199

1

According to the fluid mosaic model of cell membranes, which of the following is a true statement about membrane phospholipids?

Selecciona una de las siguientes respuestas posibles:

They can move laterally along the plane of the membrane.
They frequently flip-flop from one side of the membrane to the other.
They occur in an uninterrupted bilayer, with membrane proteins restricted to the surface of the membrane.
They are free to depart from the membrane and dissolve in the surrounding solution.
They have hydrophilic tails in the interior of the membrane

Explicación

Pregunta 57 de 199

1

Which of the following would likely move through the lipid bilayer of a plasma membrane most rapidly?

Selecciona una de las siguientes respuestas posibles:

CO2
an amino acid
glucose
K+
starch

Explicación

Pregunta 58 de 199

1

Which of the following statements is correct about diffusion?

Selecciona una de las siguientes respuestas posibles:

It is very rapid over long distances.
It requires an expenditure of energy by the cell.
It is a passive process in which molecules move from a region of higher concentration to a region of lower concentration.
It is an active process in which molecules move from a region of lower concentration to one of higher concentration.
It requires integral proteins in the cell membrane.

Explicación

Pregunta 59 de 199

1

If a membrane protein in an animal cell is involved inthe cotransport of glucose and sodiumions into the cell, which of the following is most likely true?

Selecciona una de las siguientes respuestas posibles:

The sodium ions are moving down their electrochemical gradient while glucose is moving up.
Glucose is entering the cell along its concentration gradient.
Sodium ions can move down their electrochemical gradient through the cotransporter whether or not glucose is present outside the cell.
Potassium ions move across the same gradient as sodium ions.
A substance that blocked sodium ions from binding to the cotransport protein would also block the transport of glucose.

Explicación

Pregunta 60 de 199

1

Which of the following statements about xylem is incorrect?

Selecciona una de las siguientes respuestas posibles:

It conducts material upward.
It conducts materials within dead cells.
It transports mainly sugars and amino acids.
It has a lower water potential than soil does.
No energy input from the plant is required for xylem transport.

Explicación

Pregunta 61 de 199

1

Root hairs are most important to a plant because they

Selecciona una de las siguientes respuestas posibles:

anchor a plant in the soil
store starches.
increase the surface area for absorption.
provide a habitat for nitrogen-fixing bacteria.
contain xylem tissue.

Explicación

Pregunta 62 de 199

1

What is the role of proton pumps in root hair cells?

Selecciona una de las siguientes respuestas posibles:

establish ATP gradients
acquire minerals from the soil
pressurize xylem transport
eliminate excess electrons
A and D only

Explicación

Pregunta 63 de 199

1

A water molecule could move all the way through a plant from soil to root to leaf to air and pass through a living cell only once. This living cell would be a part of which structure?

Selecciona una de las siguientes respuestas posibles:

the Casparian strip
a guard cell
the root epidermis
the endodermis
the root cortex

Explicación

Pregunta 64 de 199

1

What is the main force by which most of the water within xylem vessels moves toward the top of a tree?

Selecciona una de las siguientes respuestas posibles:

active transport of ions into the stele
atmospheric pressure on roots
evaporation of water through stoma
the force of root pressure
osmosis in the root

Explicación

Pregunta 65 de 199

1

Which of the following are defenses that some plants use against herbivory?

Selecciona una de las siguientes respuestas posibles:

production of the unusual amino acid canavanine
release of volatile compounds that attract parasitoid wasps
association of plant tissues with mycorrhizae
A and B only
A, B, and C

Explicación

Pregunta 66 de 199

1

Plants are affected by an array of pathogens. Which of the following is not a plant defense against disease?

Selecciona una de las siguientes respuestas posibles:

cells near the point of infection destroying themselves to prevent the spread of the infection
production of chemicals that kill pathogens
acquiring gene-for-gene recognition that allows specific proteins to interact so that the plant can produce defenses against the pathogen
a waxy cuticle that pathogens have trouble penetrating
All of the above are plant defenses against disease.

Explicación

Pregunta 67 de 199

1

The transduction pathway that activates systemic acquired resistance in plants is initially signaled by

Selecciona una de las siguientes respuestas posibles:

antisense RNA.
Pfr phytochrome.
salicylic acid.
abscisic acid.
red, but not far-red, light.

Explicación

Pregunta 68 de 199

1

A short-day plant exposed to nights longer than the minimum for flowering but interrupted by short flashes of light will flower.

Selecciona uno de los siguientes:

VERDADERO
FALSO

Explicación

Pregunta 69 de 199

1

A long-day plant will flower only when the night is longer than a critical value.

Selecciona uno de los siguientes:

VERDADERO
FALSO

Explicación

Pregunta 70 de 199

1

An example of a properly functioning homeostatic control system is seen when

Selecciona una de las siguientes respuestas posibles:

the level of glucose in the blood is abnormally high whether or not a meal has been eaten.
a blood cell shrinks when placed in a solution of salt and water.
the core body temperature of a runner rises gradually from 37°C to 45°C.
the kidneys excrete salt into the urine when dietary salt levels rise.
the blood pressure increases in response to an increase in blood volume.

Explicación

Pregunta 71 de 199

1

Positive feedback has occurred when

Selecciona una de las siguientes respuestas posibles:

an increase in blood sugar increases the secretion of a hormone that stimulates the movement of sugar out of the blood.
a decrease in blood sugar increases the secretion of a hormone that increases the conversion of glycogen to glucose.
uterine contractions needed for the birthing process are expedited by the pressure of a moving baby in its mother's uterus.
an increase in calcium concentration increases the secretion of a hormone that promotes the storage of calcium in bone.
a decrease in blood calcium increases the amount of the hormone that causes the release of calcium from bone.

Explicación

Pregunta 72 de 199

1

In a survivably cold environment, an ectotherm is more likely to survive an extended period of food deprivation than would an equally sized endotherm because the ectotherm

Selecciona una de las siguientes respuestas posibles:

invests little energy in temperature regulation.
has greater insulation on its body surface.
maintains a higher basal metabolic rate.
metabolizes its stored energy more readily than can the endotherm.
expends more energy per kg of body mass than does the endotherm.

Explicación

Pregunta 73 de 199

1

Humans can lose, but cannot gain, heat through the process of

Selecciona una de las siguientes respuestas posibles:

conduction.
evaporation.
radiation.
metabolism.
convection.

Explicación

Pregunta 74 de 199

1

An example of an ectothermic organism that has few or no behavioral options when it comes to its ability to adjust its body temperature is a

Selecciona una de las siguientes respuestas posibles:

sea star, a marine invertebrate.
bluefin tuna, a predatory fish.
terrestrial lizard.
honeybee in a hive.
hummingbird.

Explicación

Pregunta 75 de 199

1

Endothermy

Selecciona una de las siguientes respuestas posibles:

is only seen in mammals
is a term equivalent to "cold-blooded."
involves the production of heat through metabolism
is only seen in insects
is a characteristic of most animals

Explicación

Pregunta 76 de 199

1

An example of an organism that has only behavioral controls over its body temperature is the

Selecciona una de las siguientes respuestas posibles:

green frog.
penguin.
bluefin tuna
house sparrow.
gray wolf.

Explicación

Pregunta 77 de 199

1

The temperature-regulating center of vertebrate animals is located in the

Selecciona una de las siguientes respuestas posibles:

medulla oblongata.
thyroid gland.
hypothalamus.
subcutaneous layer of the skin.
liver

Explicación

Pregunta 78 de 199

1

Ingested foods inside the digestive tract of snakes are typically digested by

Selecciona una de las siguientes respuestas posibles:

biosynthesis.
enzymatic hydrolysis
uric acid.
chemiosmosis.
metabolic heat.

Explicación

Pregunta 79 de 199

1

What does the difference in temperature between arteries and veins in the goose's legs indicate?

Selecciona una de las siguientes respuestas posibles:

The legs need to be kept cool so that muscles will function well.
The feet need to be kept very warm so they do not freeze in water.
Heat loss is proportional to the difference in temperature inside and outside, so minimizing the difference means the goose will lose less heat.
Arterial blood helps return heat to the core of the goose.
Warm venous blood is necessary to keep the goose's feet from freezing.

Explicación

Pregunta 80 de 199

1

Both the eye and the respiratory tract are protected against infections by which of the
following?

Selecciona una de las siguientes respuestas posibles:

the secretion of lysozyme onto their surface
the mucous membranes that cover their surface
the secretion of complement proteins
the release of slightly acidic secretions
interferons produced by immune cells

Explicación

Pregunta 81 de 199

1

Which statement about the complement system is true?

Selecciona una de las siguientes respuestas posibles:

These proteins are involved in innate immunity and not acquired immunity.
These proteins are secreted by cytotoxic T cells and other CD8 cells.
This group of proteins includes interferons and interleukins.
These proteins are one group of antimicrobial proteins acting together in cascade fashion.
These proteins act individually to attack and lyse microbes.

Explicación

Pregunta 82 de 199

1

Which cells and which signaling molecules are responsible for initiating an inflammatory response?

Selecciona una de las siguientes respuestas posibles:

phagocytes: lysozymes
phagocytes: chemokines
dendritic cells: interferons
mast cells: histamines
lymphocytes: interferons

Explicación

Pregunta 83 de 199

1

Septic shock, a systemic response including high fever and low blood pressure, is a response to

Selecciona una de las siguientes respuestas posibles:

specific forms of viruses.
certain bacterial infections.
the presence of natural killer cells.
a fever of >103°F in adults.
increased production of neutrophils

Explicación

Pregunta 84 de 199

1

If a newborn were accidentally given a drug that destroyed the thymus, what would most likely happen?

Selecciona una de las siguientes respuestas posibles:

His cells would lack class I MHC molecules on their surface.
His immune system would not function.
Genetic rearrangement of antigen receptors would not occur.
His T cells would not mature and differentiate appropriately.
His B cells would be reduced in number.

Explicación

Pregunta 85 de 199

1

The clonal selection theory is an explanation for how

Selecciona una de las siguientes respuestas posibles:

a single type of stem cell can produce both red blood cells and white blood cells.
V gene and J gene segments are rearranged
an antigen can provoke development of very few cells to result in production of high levels of specific antibodies.
HIV can disrupt the immune system.
macrophages can recognize specific T cells and B cells.

Explicación

Pregunta 86 de 199

1

When would B cells produce effector cells?

Selecciona una de las siguientes respuestas posibles:

between 0 and 7 days
between 7 and 14 days
between 28 and 35 days
A and B
A and C

Explicación

Pregunta 87 de 199

1

When would memory cells be produced?

Selecciona una de las siguientes respuestas posibles:

between 0 and 7 days
between 7 and 14 days
between 28 and 35 days
between 35 and 42 days
both A and C

Explicación

Pregunta 88 de 199

1

Which of the following differentiates T cells and B cells?

Selecciona una de las siguientes respuestas posibles:

T cells but not B cells are stimulated to increase the rate of their cell cycles.
Only B cells are produced from stem cells of the bone marrow.
T cells but not B cells can directly attack and destroy invading pathogens.
T cells but not B cells have surface markers.
Only B cells take part in cell-mediated immunity.

Explicación

Pregunta 89 de 199

1

The MHC is important in a T cell's ability to

Selecciona una de las siguientes respuestas posibles:

recognize specific parasitic pathogens.
distinguish self from nonself.
identify specific bacterial pathogens.
identify specific viruses.
recognize differences among types of cancer.

Explicación

Pregunta 90 de 199

1

The following events occur when a mammalian immune system first encounters a
pathogen. Which shows the correct sequence in which they occur?
I. Pathogen is destroyed.
II. Lymphocytes secrete antibodies.
III. Antigenic determinants from pathogen bind to antigen receptors on lymphocytes.
IV. Lymphocytes specific to antigenic determinants from pathogen become numerous.
V. Only memory cells remain.

Selecciona una de las siguientes respuestas posibles:

I → III → II → IV → V
III → II → I → V → IV
II → I → IV → III → V
IV → II → III → I → V
III → IV → II → I → V

Explicación

Pregunta 91 de 199

1

Which cell type interacts with both the humoral and cell-mediated immune
pathways?

Selecciona una de las siguientes respuestas posibles:

plasma cells
helper T cells
natural killer cells
CD8 cells
cytotoxic T cells

Explicación

Pregunta 92 de 199

1

Which of the following is accounted for by immunological memory?

Selecciona una de las siguientes respuestas posibles:

the human body's ability to distinguish self from nonself
the observation that some strains of the pathogen that causes dengue fever cause worse
disease than others
the ability of a helper T cell to signal B cells via cytokines
the ancient observation that someone who had recovered from the plague could safely care
for those newly diseased
the ability of the immune system to present antigen fragments in association with MHC
antigens

Explicación

Pregunta 93 de 199

1

An otherwise healthy student in your class is infected with EBV, the virus that causes infectious
mononucleosis. The same student had already been infected when she was a child, and she had
merely experienced a mild sore throat and swollen lymph nodes in her neck. This time, though
infected, she does not get sick. The EBV antigen fragments will be presented by the virus-infected cells along with which of
the following?

Selecciona una de las siguientes respuestas posibles:

complement
antibodies
class I MHC molecules
class II MHC molecules
Dendritic cells

Explicación

Pregunta 94 de 199

1

A nonfunctional CD4 protein on a helper T cell would result in the helper T cell being unable
to

Selecciona una de las siguientes respuestas posibles:

respond to T-independent antigens.
lyse tumor cells.
stimulate a cytotoxic T cell.
interact with a class I MHC-antigen complex
interact with a class II MHC-antigen complex.

Explicación

Pregunta 95 de 199

1

Naturally acquired passive immunity would involve the

Selecciona una de las siguientes respuestas posibles:

injection of vaccine.
ingestion of interferon.
placental transfer of antibodies.
absorption of pathogens through mucous membranes.
injection of antibodies.

Explicación

Pregunta 96 de 199

1

What accounts for antibody switching (i.e., the switch of one B cell from producing one class
of antibody to another antibody class that is responsive to the same antigen)?

Selecciona una de las siguientes respuestas posibles:

mutation in the genes of that B cell, induced by exposure to the antigen
the rearrangement of V region genes in that clone of responsive B cells
a switch in the kind of antigen-presenting cell that is involved in the immune response
a patient's reaction to the first kind of antibody made by the plasma cells
the shuffling of exons for one C region type to another attached to the V-J transcript

Explicación

Pregunta 97 de 199

1

In which of the cases could the mother exhibit an anti-Rh-factor reaction to the
developing fetus?

Selecciona una de las siguientes respuestas posibles:

Case 1 only
Case 3 only
Cases 1 and 2 only
Cases 1, 2, and 3
It cannot be determined from the data given.

Explicación

Pregunta 98 de 199

1

When an individual is subject to short-term starvation, most available food is used to provide energy(metabolism) rather than building blocks (growth and repair). Which hormone would be particularly active intimes of food shortage?

Selecciona una de las siguientes respuestas posibles:

epinephrine
glucagon
oxytocin
antidiuretic hormone
insulin

Explicación

Pregunta 99 de 199

1

Based on their effects, which pair below could be considered antagonistic?

Selecciona una de las siguientes respuestas posibles:

prostaglandin F and nitric oxide
growth hormone and ecdysone
endocrine and exocrine glands
hormones and target cells
neurosecretory cells and neurotransmitters

Explicación

Pregunta 100 de 199

1

For this pair of items, choose the option that best describes their relationship.
(A) The number of purines in the DNA strand 5ʹ-AAGAGGAGAAA-3ʹ
(B) The number of pyrimidines in the DNA strand 5ʹ-AAGAGGAGAAA-3ʹ

Selecciona una de las siguientes respuestas posibles:

Item (A) is greater than item (B).
Item (A) is less than item (B).
Item (A) is exactly or very approximately equal to item (B).
Item (A) may stand in more than one of the above relations to item (B).

Explicación

Pregunta 101 de 199

1

Which of the following is not a polymer?

Selecciona una de las siguientes respuestas posibles:

glucose
starch
cellulose
chitin
DNA

Explicación

Pregunta 102 de 199

1

The molecular formula for glucose is C6H12O6. What would be the molecular formula for a
molecule made by linking three glucose molecules together by dehydration reactions?

Selecciona una de las siguientes respuestas posibles:

C18H36O18
C18H30O15
C6H10O5
C18H10O15
C3H6O3

Explicación

Pregunta 103 de 199

1

Which of the following descriptors is true of the molecule shown in Figure 5.1?

Selecciona una de las siguientes respuestas posibles:

hexose
fructose
glucose
A and B only
A and C only

Explicación

Pregunta 104 de 199

1

Which of the following statements is true regarding the molecule illustrated in Figure 5.2?

Selecciona una de las siguientes respuestas posibles:

It is a saturated fatty acid.
A diet rich in this molecule may contribute to atherosclerosis.
Molecules of this type are usually liquid at room temperature.
A and B only
A, B and C

Explicación

Pregunta 105 de 199

1

Which of the following statements is true regarding the molecule illustrated in Figure 5.3?

Selecciona una de las siguientes respuestas posibles:

It is a saturated fatty acid.
A diet rich in this molecule may contribute to atherosclerosis.
Molecules of this type are usually liquid at room temperature
A and B only
A, B and C

Explicación

Pregunta 106 de 199

1

What is the structure shown in Figure 5.4?

Selecciona una de las siguientes respuestas posibles:

starch molecule
protein molecule
steroid molecule
cellulose molecule
phospholipid molecule

Explicación

Pregunta 107 de 199

1

At which bond would water need to be added to achieve hydrolysis of the peptide, back to
its component amino acid?

Selecciona una de las siguientes respuestas posibles:

A
B
C
D
E

Explicación

Pregunta 108 de 199

1

Which bond is a peptide bond?

Selecciona una de las siguientes respuestas posibles:

A
B
C
D
E

Explicación

Pregunta 109 de 199

1

Which bond is closest to the N-terminus of the molecule?

Selecciona una de las siguientes respuestas posibles:

A
B
C
D
E

Explicación

Pregunta 110 de 199

1

The structure depicted in Figure 5.7 shows the

Selecciona una de las siguientes respuestas posibles:

1-4 linkage of the α glucose monomers of starch
1-4 linkage of the β glucose monomers of cellulose.
double helical structure of a DNA molecule.
α helix secondary structure of a polypeptide.
β pleated sheet secondary structure of a polypeptide

Explicación

Pregunta 111 de 199

1

Which of the following best describes the flow of information in eukaryotic cells?

Selecciona una de las siguientes respuestas posibles:

DNA → RNA → proteins
RNA → proteins → DNA
proteins → DNA → RNA
RNA → DNA → proteins
DNA → proteins → RNA

Explicación

Pregunta 112 de 199

1

If a DNA sample were composed of 10% thymine, what would be the percentage of
guanine?

Selecciona una de las siguientes respuestas posibles:

10
20
40
80
impossible to tell from the information given

Explicación

Pregunta 113 de 199

1

If one strand of a DNA molecule has the sequence of bases 5ʹATTGCA3ʹ, the other
complementary strand would have the sequence

Selecciona una de las siguientes respuestas posibles:

5ʹTAACGT3ʹ
3ʹTAACGT5ʹ.
5ʹUAACGU3ʹ
3ʹUAACGU5ʹ.
5ʹUGCAAU3ʹ.

Explicación

Pregunta 114 de 199

1

Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules?

Selecciona una de las siguientes respuestas posibles:

lipids
starches
proteins
steroids
glucose

Explicación

Pregunta 115 de 199

1

Under which of the following conditions would you expect to find a cell with a majority of "free" ribosomes (not connected to the ER)?

Selecciona una de las siguientes respuestas posibles:

a cell that is secreting proteins
a cell that is producing cytoplasmic enzymes
a cell that is constructing its cell wall or extracellular matrix
a cell that is digesting food particles
a cell that is enlarging its vacuole

Explicación

Pregunta 116 de 199

1

Which type of organelle is primarily involved in the synthesis of oils, phospholipids, and steroids?

Selecciona una de las siguientes respuestas posibles:

smooth endoplasmic reticulum
lysosome
ribosome
mitochondrion
contractile vacuole

Explicación

Pregunta 117 de 199

1

The Golgi apparatus has a polarity or sidedness to its structure and function. Which of the following statements CORRECTLY describes this polarity?

Selecciona una de las siguientes respuestas posibles:

Transport vesicles fuse with one side of the Golgi and leave from the opposite side.
Proteins in in the membrane of the Golgi may be sorted and modified as they move from one side of the Golgi to the other.
Lipids in the membrane of the Golgi may be sorted and modified as they move from one side of the Golgi to the other.
Soluble proteins in the cisternae (interior) of the Golgi may be sorted and modified as they move from one side of the Golgi to the other.
All of the above correctly describe polar characteristics of the Golgi function.

Explicación

Pregunta 118 de 199

1

Which structure is the site of the synthesis of proteins that may be exported from the cell?

Selecciona una de las siguientes respuestas posibles:

rough ER
lysosomes
plasmodesmata
Golgi vesicles
free cytoplasmic ribosomes

Explicación

Pregunta 119 de 199

1

In animal cells, hydrolytic enzymes are packaged to prevent general destruction of cellular components. Which of the following organelles functions in this compartmentalization?

Selecciona una de las siguientes respuestas posibles:

chloroplast
lysosome
central vacuole
peroxisome
glyoxysome

Explicación

Pregunta 120 de 199

1

Which of the following is a compartment that often takes up much of the volume of a plant cell?

Selecciona una de las siguientes respuestas posibles:

lysosome
vacuole
mitochondrion
Golgi apparatus
peroxisome

Explicación

Pregunta 121 de 199

1

Which is one of the main energy transformers of cells?

Selecciona una de las siguientes respuestas posibles:

lysosome
vacuole
mitochondrion
Golgi apparatus
peroxisome

Explicación

Pregunta 122 de 199

1

Which of the following contains enzymes that transfer hydrogen from various substrates to oxygen?

Selecciona una de las siguientes respuestas posibles:

lysosome
vacuole
mitochondrion
Golgi apparatus
peroxisome

Explicación

Pregunta 123 de 199

1

Grana, thylakoids, and stroma are all components found in

Selecciona una de las siguientes respuestas posibles:

vacuoles.
chloroplasts.
mitochondria.
lysosomes.
nuclei.

Explicación

Pregunta 124 de 199

1

A cell has the following molecules and structures: enzymes, DNA, ribosomes, plasma membrane, and mitochondria. It could be a cell from

Selecciona una de las siguientes respuestas posibles:

a bacterium.
an animal, but not a plant.
a plant, but not an animal.
a plant or an animal
any kind of organism

Explicación

Pregunta 125 de 199

1

Reactants capable of interacting to form products in a chemical reaction must first overcome a thermodynamic barrier known as the reaction's

Selecciona una de las siguientes respuestas posibles:

entropy
activation energy.
equilibrium point.
endothermic level.
free-energy content.

Explicación

Pregunta 126 de 199

1

Which curve represents the behavior of an enzyme taken from a bacterium that lives in hot springs at temperatures of 70oC or higher?

Selecciona una de las siguientes respuestas posibles:

1
2
3
4
5

Explicación

Pregunta 127 de 199

1

Which curve was most likely generated from analysis of an enzyme form a human stomach where conditions are strongly acidic?

Selecciona una de las siguientes respuestas posibles:

1
2
3
4
5

Explicación

Pregunta 128 de 199

1

Which of the following terms best describes the forward reaction in Figure 8.1?

Selecciona una de las siguientes respuestas posibles:

endergonic, ∆G > 0
exergonic, ∆G < 0
endergonic, ∆G < 0
exergonic, ∆G > 0
chemical equilibrium, ∆G = 0

Explicación

Pregunta 129 de 199

1

Assume that the reaction in Figure 8.1 has a ΔG of -5.6 kcal/mol. Which of the following would be true?

Selecciona una de las siguientes respuestas posibles:

The reaction could be coupled to power an endergonic reaction with a ΔG of +6.2 kcal/mol.
The reaction could be coupled to power an exergonic reaction with a ΔG of +8.8 kcal/mol.
The reaction would result in a decrease in entropy (S) and an increase in the total energy content (H) of the system.
The reaction would result in an increase in entropy (S) and a decrease in the total energy content (H) of the system.
The reaction would result in products (C + D) with a greater free-energy content than in the initial reactants (A + B).

Explicación

Pregunta 130 de 199

1

Paracrine signaling

Selecciona una de las siguientes respuestas posibles:

involves secreting cells acting on nearby target cells by discharging a local regulator into the extracellular fluid.
requiresnerve cells to release a neurotransmitter into the synapse
occurs only in paracrine yeast cells.
has been found in plants but not animals.
involves mating factors attaching to target cells and causing production of new paracrine cells.

Explicación

Pregunta 131 de 199

1

What would be true for the signaling system in an animal cell that lacks the ability to produce GTP?

Selecciona una de las siguientes respuestas posibles:

It would not be able to activate and inactivate the G protein on the cytoplasmic side of the plasma membrane.
It could activate only the epinephrine system.
It would be able to carry out reception and transduction, but would not be able to respond to a signal.
Only A and C are true.
A, B, and C are true.

Explicación

Pregunta 132 de 199

1

Up to 60% of all medicines used today exert their effects by influencing what structures in the cell membrane?

Selecciona una de las siguientes respuestas posibles:

tyrosine-kinases receptors
ligand-gated ion channel receptors
growth factors
G proteins
cholesterol

Explicación

Pregunta 133 de 199

1

Which of the following are chemical messengers that pass through the plasma membrane of cells & have receptor molecules in the cytoplasm?

Selecciona una de las siguientes respuestas posibles:

Insulin
Testosterone
cAMP
Ephinephrine

Explicación

Pregunta 134 de 199

1

A major group of G protein-coupled receptors contains seven transmembrane α helices. The amino end of the protein lies at the exterior of the plasma membrane. Loops of amino acids connect the helices either at the exterior face or on the cytosol face of the membrane. The loop on the cytosol side between helices 5 and 6 is usually substantially longer than the others.

Where would you expect to find the carboxyl end?

Selecciona una de las siguientes respuestas posibles:

at the exterior surface
at the cytosol surface
connected with the loop at H5 and H6
between the membrane layers

Explicación

Pregunta 135 de 199

1

One of the major categories of receptors in the plasma membrane reacts by forming dimers, adding phosphate groups, and then activating relay proteins. Which type does this?

Selecciona una de las siguientes respuestas posibles:

G protein-coupled receptors
ligand-gated ion channels
steroid receptors
receptor tyrosine kinases

Explicación

Pregunta 136 de 199

1

Sutherland discovered that epinephrine signals

Selecciona una de las siguientes respuestas posibles:

a decrease in levels of cAMP as a result of bypassing the plasma membrane.
lower blood glucose by binding to liver cells.
interactions with insulin inside muscle cells.
interactions directly with glycogen phosphorylase.
elevation of cytosolic concentrations of cyclic AMP.

Explicación

Pregunta 137 de 199

1

Which of the following describes cell communication systems?

Selecciona una de las siguientes respuestas posibles:

Cell signaling evolved more recently than systems such as the immune system of vertebrates.
Communicating cells are usually close together.
Most signal receptors are bound to the outer membrane of the nuclear envelope.
Lipid phosphorylation is a major mechanism of signal transduction.
In response to a signal, the cell may alter activities by changes in cytosol activity or intranscription of RNA.

Explicación

Pregunta 138 de 199

1

Which of the following most likely would be an immediate result of growth factor binding to its receptor?

Selecciona una de las siguientes respuestas posibles:

protein kinase activity
adenylyl cyclase activity
GTPase activity
protein phosphatase activity
phosphorylase activity

Explicación

Pregunta 139 de 199

1

Adenylyl cyclase has the opposite effect of which of the following?

Selecciona una de las siguientes respuestas posibles:

protein kinase
protein phosphatase
phosphodiesterase
phosphorylase
GTPase

Explicación

Pregunta 140 de 199

1

If a pharmaceutical company wished to design a drug to maintain low blood sugar levels, oneapproach might be to

Selecciona una de las siguientes respuestas posibles:

design a compound that blocks epinephrine receptor activation.
design a compound that inhibits cAMP production in liver cells.
design a compound that inhibits phosphorylase activity.
design a compound to block G-protein activity in liver cells.
All of the above are possible approaches.

Explicación

Pregunta 141 de 199

1

Which of the following statements is true?

Selecciona una de las siguientes respuestas posibles:

When signal molecules first bind to receptor tyrosine kinases, the receptors phosphorylate anumber of nearby molecules
In response to some G-protein-mediated signals, a special type of lipid molecule associated with the plasma membrane is cleaved to form IP3 and calcium.
In most cases, signal molecules interact with the cell at the plasma membrane and then enter the cell and eventually the nucleus.
Toxins such as those that cause botulism and cholera interfere with the ability of activated G proteins to hydrolyze GTP to GDP, resulting in phosphodiesterase activity in the absence of an appropriate signal molecule.
Protein kinase A activation is one possible result of signal molecules binding to G protein-linked receptors.

Explicación

Pregunta 142 de 199

1

One inhibitor of cGMP is Viagra. It provides a signal that leads to dilation of blood vesselsand increase of blood in the penis, facilitating erection. cGMP is inhibited, therefore the signal isprolonged. The original signal that is now inhibited would have

Selecciona una de las siguientes respuestas posibles:

hydrolyzed cGMP to GMP.
hydrolyzed GTP to GDP
phosphorylated GDP.
dephosphorylated cGMP.
removed GMP from the cell.

Explicación

Pregunta 143 de 199

1

The nucleus and most of the organelles in a neuron are located in the

Selecciona una de las siguientes respuestas posibles:

dendritic region.
axon hillock.
axon.
cell body.
axon terminals

Explicación

Pregunta 144 de 199

1

For a neuron with an initial membrane potential at -70 mV, an increase in the movement of potassium ions out of that neuron's cytoplasm would result in

Selecciona una de las siguientes respuestas posibles:

the depolarization of the neuron
the hyperpolarization of the neuron
the replacement of potassium ions with sodium ions.
the replacement of potassium ions with calcium ions
the neuron switching on its sodium-potassium pump to restore the initial conditions

Explicación

Pregunta 145 de 199

1

Although the membrane of a "resting" neuron is highly permeable to potassium ions, its membrane potential does not exactly match the equilibrium potential for potassium because the neuronal membrane is also

Selecciona una de las siguientes respuestas posibles:

fully permeable to sodium ions.
slightly permeable to sodium ions
fully permeable to calcium ions.
impermeable to sodium ions
highly permeable to chloride ions.

Explicación

Pregunta 146 de 199

1

The operation of the sodium-potassium "pump" moves

Selecciona una de las siguientes respuestas posibles:

sodium and potassium ions into the cell.
sodium and potassium ions out of the ce
sodium ions into the cell and potassium ions out of the cell.
sodium ions out of the cell and potassium ions into the cell.
sodium and potassium ions into the mitochondria.

Explicación

Pregunta 147 de 199

1

A "resting" motor neuron is expected to

Selecciona una de las siguientes respuestas posibles:

release lots of acetylcholine.
have high permeability to sodium ions.
be equally permeable to sodium and potassium ions.
exhibit a resting potential that is more negative than the "threshold" potential.
have a higher concentration of sodium ions on the inside of the cell than on the outside

Explicación

Pregunta 148 de 199

1

The "threshold" potential of a membrane

Selecciona una de las siguientes respuestas posibles:

is the point of separation from a living to a dead neuron.
is the lowest frequency of action potentials a neuron can produce.
is the minimum hyperpolarization needed to prevent the occurrence of action potentials.
is the minimum depolarization needed to operate the voltage-gated sodium and potassium channels.
is the peak amount of depolarization seen in an action potential.

Explicación

Pregunta 149 de 199

1

A toxin that binds specifically to voltage-gated sodium channels in axons would be expected to

Selecciona una de las siguientes respuestas posibles:

prevent the hyperpolarization phase of the action potential.
prevent the depolarization phase of the action potential.
prevent graded potentials
increase the release of neurotransmitter molecules.
have most of its effects on the dendritic region of a neuron.

Explicación

Pregunta 150 de 199

1

After the depolarization phase of an action potential, the resting potential is restored by

Selecciona una de las siguientes respuestas posibles:

the opening of sodium activation gates.
the opening of voltage-gated potassium channels and the closing of sodium channels.
a decrease in the membrane's permeability to potassium and chloride ions.
a brief inhibition of the sodium-potassium pump
the opening of more voltage-gated sodium channels.

Explicación

Pregunta 151 de 199

1

The membrane potential is closest to the equilibrium potential for potassium at label

Selecciona una de las siguientes respuestas posibles:

A
B
C
D
E

Explicación

Pregunta 152 de 199

1

The membrane's permeability to sodium ions is at its maximum at label

Selecciona una de las siguientes respuestas posibles:

A
B
C
D
E

Explicación

Pregunta 153 de 199

1

The minimum graded depolarization needed to operate the voltage-gated sodium and potassium channels is indicated by the label

Selecciona una de las siguientes respuestas posibles:

A
B
C
D
E

Explicación

Pregunta 154 de 199

1

The cell is not hyperpolarized; however, repolarization is in progress, as the sodium channels are closing or closed, and many potassium channels have opened at label

Selecciona una de las siguientes respuestas posibles:

A
B
C
D
E

Explicación

Pregunta 155 de 199

1

The neuronal membrane is at its resting potential at label

Selecciona una de las siguientes respuestas posibles:

A
B
C
D
E

Explicación

Pregunta 156 de 199

1

In the sequence of permeability changes for a complete action potential, the first of these events that occurs is

Selecciona una de las siguientes respuestas posibles:

the activation of the sodium-potassium "pump."
the inhibition of the sodium-potassium "pump."
the opening of voltage-gated sodium channels.
the closing of voltage-gated potassium channels.
the opening of voltage-gated potassium channels.

Explicación

Pregunta 157 de 199

1

Neurotransmitters are released from axon terminals via

Selecciona una de las siguientes respuestas posibles:

osmosis.
active transport.
diffusion.
transcytosis.
exocytosis.

Explicación

Pregunta 158 de 199

1

The observation that the acetylcholine released into the junction between a motor neuron and a skeletal muscle binds to a sodium channel and opens it is an example of

Selecciona una de las siguientes respuestas posibles:

a voltage-gated sodium channel.
a voltage-gated potassium channel.
a ligand-gated sodium channel.
a second-messenger-gated sodium channel.
a chemical that inhibits action potentials.

Explicación

Pregunta 159 de 199

1

An inhibitory postsynaptic potential (IPSP) occurs in a membrane made more permeable to

Selecciona una de las siguientes respuestas posibles:

potassium ions.
sodium ions.
calcium ions.
ATP.
all neurotransmitter molecules.

Explicación

Pregunta 160 de 199

1

The activity of acetylcholine in a synapse is terminated by

Selecciona una de las siguientes respuestas posibles:

its active transport across the presynaptic membrane.
its diffusion across the presynaptic membrane.
its active transport across the postsynaptic membrane
its diffusion across the postsynaptic membrane.
its degradation by a hydrolytic enzyme on the postsynaptic membrane

Explicación

Pregunta 161 de 199

1

When several EPSPs arrive at the axon hillock from different dendritic locations, depolarizing the postsynaptic cell to threshold for an action potential, this is an example of

Selecciona una de las siguientes respuestas posibles:

temporal summation.
spatial summation.
tetanus.
the refractory state.
an action potential with an abnormally high peak of depolarization.

Explicación

Pregunta 162 de 199

1

Functionally, which cellular location is the neuron's "decision-making site" as to whether or not an action potential will be initiated?

Selecciona una de las siguientes respuestas posibles:

axonal membranes
axon hillocks
dendritic membranes
mitochondrial membranes
presynaptic membranes

Explicación

Pregunta 163 de 199

1

Which of the following types of reactions would decrease the entropy within a cell?

Selecciona una de las siguientes respuestas posibles:

respiration
dehydration reactions
hydrolysis
catabolism
digestion

Explicación

Pregunta 164 de 199

1

Which of the following is an example of potential rather than kinetic energy?

Selecciona una de las siguientes respuestas posibles:

the muscle contractions of a person mowing grass
water rushing over Niagara Falls
light flashes emitted by a firefly
a molecule of glucose
the flight of an insect foraging for food

Explicación

Pregunta 165 de 199

1

Which of the following is true of metabolism in its entirety in all organisms?

Selecciona una de las siguientes respuestas posibles:

Metabolism depends on a constant supply of energy from food.
Metabolism depends on an organism's adequate hydration.
Metabolism uses all of an organism's resources.
Metabolism is a property of organismal life.
Metabolism manages the increase of entropy in an organism.

Explicación

Pregunta 166 de 199

1

What is the change in free energy of a system at chemical equilibrium?

Selecciona una de las siguientes respuestas posibles:

slightly increasing
greatly increasing
slightly decreasing
greatly decreasing
no net change

Explicación

Pregunta 167 de 199

1

Chemical equilibrium is relatively rare in living cells. Which of the following could be an example of a reaction at chemical equilibrium in a cell?

Selecciona una de las siguientes respuestas posibles:

a reaction in which the free energy at equilibrium is higher than the energy content at any point away from equilibrium
a chemical reaction in which the entropy change in the reaction is just balanced by an opposite entropy change in the cell's surroundings
an endergonic reaction in an active metabolic pathway where the energy for that reaction is supplied only by heat from the environment
a chemical reaction in which both the reactants and products are not being produced or used in any active metabolic pathway
no possibility of having chemical equilibrium in any living cell

Explicación

Pregunta 168 de 199

1

When glucose monomers are joined together by glycosidic linkages to form a cellulose polymer, the changes in free energy, total energy, and entropy are as follows:

Selecciona una de las siguientes respuestas posibles:

+ΔG, +ΔH, +ΔS.
+ΔG, +ΔH, -ΔS.
+ΔG, -ΔH, -ΔS.
-ΔG, +ΔH, +ΔS.
-ΔG, -ΔH, -ΔS

Explicación

Pregunta 169 de 199

1

Which of the following best describes enthalpy (H)?

Selecciona una de las siguientes respuestas posibles:

the total kinetic energy of a system
the heat content of a chemical system
the system's entropy
the cell's energy equilibrium
the condition of a cell that is not able to react

Explicación

Pregunta 170 de 199

1

When 10,000 molecules of ATP are hydrolyzed to ADP and Pi in a test tube, about twice as much heat is liberated as when a cell hydrolyzes the same amount of ATP. Which of the following is the best explanation for this observation?

Selecciona una de las siguientes respuestas posibles:

Cells are open systems, but a test tube is a closed system.
Cells are less efficient at heat production than nonliving systems.
The hydrolysis of ATP in a cell produces different chemical products than does the reaction in a test tube.
The reaction in cells must be catalyzed by enzymes, but the reaction in a test tube does not need enzymes.
Reactant and product concentrations in the test tube are different from those in the cell.

Explicación

Pregunta 171 de 199

1

What term is used to describe the transfer of free energy from catabolic pathways to anabolic pathways?

Selecciona una de las siguientes respuestas posibles:

feedback regulation
bioenergetics
energy coupling
entropy
cooperativity

Explicación

Pregunta 172 de 199

1

When chemical, transport, or mechanical work is done by an organism, what happens to the heat generated?

Selecciona una de las siguientes respuestas posibles:

It is used to power yet more cellular work.
It is used to store energy as more ATP.
It is used to generate ADP from nucleotide precursors.
It is lost to the environment.
It is transported to specific organs such as the brain.

Explicación

Pregunta 173 de 199

1

A number of systems for pumping across membranes are powered by ATP. Such ATP-powered pumps are often called ATPases although they don't often hydrolyze ATP unless they are simultaneously transporting ions. Small increases in calcium ions in the cytosol trigger a number of different intracellular reactions, so the cells must keep the calcium concentration quite low. Muscle cells also transport calcium from the cytosol into the membranous system called the sarcoplasmic reticulum (SR). If a muscle cell cytosol has a free calcium ion concentration of 10-7 in a resting cell, while the concentration in the SR can be 10-2, then how is the ATPase acting?

Selecciona una de las siguientes respuestas posibles:

The ATP must be powering an inflow of calcium from the outside of the cell into the SR
ATP must be transferring Pi to the SR to enable this to occur.
ATPase activity must be pumping calcium from the cytosol to the SR against the concentration gradient.
The calcium ions must be diffusing back into the SR along the concentration gradient.
The route of calcium ions must be from SR to the cytosol, to the cell's environment.

Explicación

Pregunta 174 de 199

1

What is the term for metabolic pathways that release stored energy by breaking down complex molecules?

Selecciona una de las siguientes respuestas posibles:

anabolic pathways
catabolic pathways
fermentation pathways
thermodynamic pathways
bioenergetic pathways

Explicación

Pregunta 175 de 199

1

Which of the following statements describes the results of this reaction?
C₆H₁₂O₆ + 6 O₂ → 6 CO₂ + 6 H₂O + Energy

Selecciona una de las siguientes respuestas posibles:

C₆H₁₂O₆ is oxidized and O₂ is reduced.
O₂ is oxidized and H₂O is reduced.
CO₂ is reduced and O₂ is oxidized
C₆H₁₂O₆ is reduced and CO₂ is oxidized.
O₂ is reduced and CO₂ is oxidized

Explicación

Pregunta 176 de 199

1

Where does glycolysis take place in eukaryotic cells?

Selecciona una de las siguientes respuestas posibles:

mitochondrial matrix
mitochondrial outer membrane
mitochondrial inner membrane
mitochondrial intermembrane space
cytosol

Explicación

Pregunta 177 de 199

1

Which step in Figure 9.1 shows a split of one molecule into two smaller molecules?

Selecciona una de las siguientes respuestas posibles:

A
B
C
D
E

Explicación

Pregunta 178 de 199

1

Starting with one molecule of glucose, the "net" products of glycolysis are

Selecciona una de las siguientes respuestas posibles:

2 NAD⁺, 2 pyruvate, and 2 ATP
2 NADH, 2 pyruvate, and 2 ATP
2 FADH₂, 2 pyruvate, and 4 ATP
6 CO₂, 2 ATP, and 2 pyruvate.
6 CO₂, 30 ATP, and 2 pyruvate

Explicación

Pregunta 179 de 199

1

Why is glycolysis described as having an investment phase and a payoff phase?

Selecciona una de las siguientes respuestas posibles:

It both splits molecules and assembles molecules
It attaches and detaches phosphate groups.
It uses glucose and generates pyruvate.
It shifts molecules from cytosol to mitochondrion.
It uses stored ATP and then forms a net increase in ATP

Explicación

Pregunta 180 de 199

1

In the presence of oxygen, the three-carbon compound pyruvate can be catabolized in the citric acid cycle. First, however, the pyruvate (1) loses a carbon, which is given off as a molecule of CO₂, (2) is oxidized to form a two-carbon compound called acetate, and (3) is bonded to coenzyme A.

These three steps result in the formation of

Selecciona una de las siguientes respuestas posibles:

acetyl CoA, O₂, and ATP.
acetyl CoA, FADH₂, and CO₂
acetyl CoA, FAD, H₂, and CO₂.
acetyl CoA, NADH, H⁺, and CO₂.
acetyl CoA, NAD⁺, ATP, and CO₂

Explicación

Pregunta 181 de 199

1

How many molecules of carbon dioxide (CO2) would be produced by five turns of the citric acid cycle?

Selecciona una de las siguientes respuestas posibles:

2
5
10
12
60

Explicación

Pregunta 182 de 199

1

Which of the following describes the sequence of electron carriers in the electron transport chain, starting with the least electronegative?

Selecciona una de las siguientes respuestas posibles:

ubiquinone (Q), cytochromes (Cyt), FMN, Fe•S
cytochromes (Cyt), FMN, ubiquinone, Fe∙S
Fe•S, FMN, cytochromes (Cyt), ubiquinone
FMN, Fe•S, ubiquinone, cytochromes (Cyt)
cytochromes (Cyt), Fe•S, ubiquinone, FMN

Explicación

Pregunta 183 de 199

1

Where does the Calvin cycle take place?

Selecciona una de las siguientes respuestas posibles:

stroma of the chloroplast
thylakoid membrane
cytoplasm surrounding the chloroplast
interior of the thylakoid (thylakoid space)
outer membrane of the chloroplast

Explicación

Pregunta 184 de 199

1

When oxygen is released as a result of photosynthesis, it is a direct by-product of

Selecciona una de las siguientes respuestas posibles:

reducing NADP⁺.
splitting water molecules.
chemiosmosis.
the electron transfer system of photosystem I
the electron transfer system of photosystem II.

Explicación

Pregunta 185 de 199

1

Figure 10.1 shows the absorption spectrum for chlorophyll a and the action spectrum for photosynthesis. Why are they different?

Selecciona una de las siguientes respuestas posibles:

Green and yellow wavelengths inhibit the absorption of red and blue wavelengths.
Bright sunlight destroys photosynthetic pigments.
Oxygen given off during photosynthesis interferes with the absorption of light.
Other pigments absorb light in addition to chlorophyll a.
Aerobic bacteria take up oxygen, which changes the measurement of the rate of photosynthesis.

Explicación

Pregunta 186 de 199

1

Assume a thylakoid is somehow punctured so that the interior of the thylakoid is no longer separated from the stroma. This damage will have the most direct effect on which of the following processes?

Selecciona una de las siguientes respuestas posibles:

the splitting of water
the absorption of light energy by chlorophyll
the flow of electrons from photosystem II to photosystem I
the synthesis of ATP
the reduction of NADP⁺

Explicación

Pregunta 187 de 199

1

In mitochondria, chemiosmosis translocates protons from the matrix into the intermembranespace, whereas in chloroplasts, chemiosmosis translocates protons from

Selecciona una de las siguientes respuestas posibles:

the stroma to the photosystem II.
the matrix to the stroma.
the stroma to the thylakoid space.
the intermembrane space to the matrix.
ATP synthase toNADP+ reductase.

Explicación

Pregunta 188 de 199

1

In thylakoids, protons travel through ATP synthase from the stroma to the thylakoid space.Therefore the catalytic "knobs" of ATP synthase would be located

Selecciona una de las siguientes respuestas posibles:

on the side facing the thylakoid space
on the ATP molecules themselves.
on the pigment molecules of PSI and PSII.
on the stroma side of the membrane.
built into the center of the thylkoid stack (granum).

Explicación

Pregunta 189 de 199

1

Compare the light reactions with the Calvin cycle of photosynthesis in plants.
Produces NADH:

Selecciona una de las siguientes respuestas posibles:

light reactions alone
the Calvin cycle alone
both the light reactions and the Calvin cycle
neither the light reactions nor the Calvin cycle
occurs in the chloroplast but is not part of photosynthesis

Explicación

Pregunta 190 de 199

1

Compare the light reactions with the Calvin cycle of photosynthesis in plants.
Requires glucose:

Selecciona una de las siguientes respuestas posibles:

light reactions alone
the Calvin cycle alone
both the light reactions and the Calvin cycle
neither the light reactions nor the Calvin cycle
occurs in the chloroplast but is not part of photosynthesis

Explicación

Pregunta 191 de 199

1

The sugar that results from three "turns" of the Calvin cycle is glyceraldehyde-3-phosphate
(G3P). Which of the following is a consequence of this?

Selecciona una de las siguientes respuestas posibles:

Formation of a moleculeof glucose would require 9 "turns."
G3P more readily forms sucrose and other disaccharides than it does monosaccharides.
Some plants would not taste sweet to us.
The formation of starch in plants involves assembling many G3P molecules, with or without further rearrangements.
G3P is easier for a plant to store.

Explicación

Pregunta 192 de 199

1

If ATP used by this plant is labeled with radioactive phosphorus, which molecules will the radioactivity be measurable after one "turn" of the cycle?

Selecciona una de las siguientes respuestas posibles:

B only
B and C only
B, C, and D only
B and E only
B, C, D, and E

Explicación

Pregunta 193 de 199

1

If the carbon atom of the incoming CO₂ molecule is labeled with a radioactive isotope of carbon, which organic molecules will be radioactively labeled after one cycle?

Selecciona una de las siguientes respuestas posibles:

E only
B, C, D, and E
C, D, and E only
B and C only
B and D only

Explicación

Pregunta 194 de 199

1

Which molecule(s) of the Calvin cycle is (are) also found in glycolysis?

Selecciona una de las siguientes respuestas posibles:

A only
C and D only
A, B, C, and E
B, C, and E
E only

Explicación

Pregunta 195 de 199

1

Evolutionary adaptations that help diverse animals directly exchange matter between cells and the environment include

Selecciona una de las siguientes respuestas posibles:

a gastrovascular activity, a two-layered body, and a torpedo-like body shape.
an external respiratory surface, a small body size, and a two-cell-layered body.
a large body volume; a long, tubular body; and a set of wings.
complex internal structures, a small body size, and a large surface area.
an unbranched internal surface, a small body size, and thick covering.

Explicación

Pregunta 196 de 199

1

Hibernation and estivation are both examples of

Selecciona una de las siguientes respuestas posibles:

acclimatization.
torpor.
evaporative cooling
nonshivering thermogenesis.
shivering thermogenesis.

Explicación

Pregunta 197 de 199

1

If you gently twist your earlobe, it does not remain distorted because it contains

Selecciona una de las siguientes respuestas posibles:

collagenous fibers.
elastin fibers.
reticular fibers.
adipose tissue.
loose connective tissue.

Explicación

Pregunta 198 de 199

1

Endothermy

Selecciona una de las siguientes respuestas posibles:

is a characteristic of most animals
involves the production of heat through metabolism
is only seen in insects
is a term equivalent to "cold-blooded"
is only seen in mammals

Explicación

Pregunta 199 de 199

1

The best time to measure the metabolic rate is when the animal

Selecciona una de las siguientes respuestas posibles:

is resting and has not eaten its first meal of the day.
is resting and has just completed its first meal of the day.
has recently eaten a sugar-free meal.
has not consumed any water for at least 48 hours.
has just completed 30 minutes of vigorous exercise.

	Creado por rweston17 hace casi 10 años

Test sobre AP BIO MIDTERM REVIEW, creado por rweston17 el 18/01/2015.

AP BIO MIDTERM REVIEW

Pregunta 1 de 199

Darwinʹs mechanism of natural selection required long time spans in order to modify species. From whom did Darwin get the concept of Earthʹs ancient age?

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 2 de 199

Charles Darwin was the first person to propose

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 3 de 199

Which of these conditions should completely prevent the occurrence of natural selection in a population over time?

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 4 de 199

Which of the following represents an idea that Darwin learned from the writings of Thomas Malthus?

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 5 de 199

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 6 de 199

To observe natural selectionʹs effects on a population, which of these must be true?

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 7 de 199

During drought years on the Galapagos, small, easily eaten seeds become rare, leaving mostly large, hard-cased seeds that only birds with large beaks can eat. If a drought persists for several years, what should one expect to result from natural selection?

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 8 de 199

Which of the following must exist in a population before natural selection can act upon that population?

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 9 de 199

How many separate species, both extant and extinct, are depicted in this tree?

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 10 de 199

Which of the five common ancestors, labeled V—Z, has given rise to the greatest number of species, both extant and extinct?

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 11 de 199

Evolutionary trees such as this are properly understood by scientists to be

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 12 de 199

Which statement best describes the evolution of pesticide resistance in a population of insects?

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 13 de 199

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 14 de 199

Of the following anatomical structures, which is homologous to the wing of a bird?

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 15 de 199

Structures as different as human arms, bat wings, and dolphin flippers contain many of the same bones, these bones having developed from very similar embryonic tissues. How do biologists interpret these similarities?

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 16 de 199

Which of the following pieces of evidence most strongly supports the common origin of all life on Earth?

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 17 de 199

Which of the following statements most detracts from the claim that the human appendix is a completely vestigial organ?

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 18 de 199

Ichthyosaurs were aquatic dinosaurs. Fossils show us that they had dorsal fins and tails, as do fish, even though their closest relatives were terrestrial reptiles that had neither dorsal fins nor aquatic tails. The dorsal fins and tails of ichthyosaurs and fish are

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 19 de 199

Monkeys of South and Central America have prehensile tails, meaning that their tails can be used to grasp objects. The tails of African and Asian monkeys are not prehensile. Which discipline is most likely to provide an evolutionary explanation for how this difference in tails came about?

Selecciona una de las siguientes respuestas posibles:

Explicación

Pregunta 20 de 199

Heterozygote advantage should be most closely linked to which of the following?

Selecciona una de las siguientes respuestas posibles:

Explicación

Darwinʹs mechanism of natural selection required long time spans in order to modify species. From whom did
Darwin get the concept of Earthʹs ancient age?

Which of these conditions should completely prevent the occurrence of natural selection in a population over
time?

During drought years on the Galapagos, small, easily eaten seeds become rare, leaving mostly large,
hard-cased seeds that only birds with large beaks can eat. If a drought persists for several years, what should
one expect to result from natural selection?

Which of the five common ancestors, labeled V—Z, has given rise to the greatest number of species, both extant
and extinct?

Structures as different as human arms, bat wings, and dolphin flippers contain many of the same bones, these
bones having developed from very similar embryonic tissues. How do biologists interpret these similarities?

Which of the following statements most detracts from the claim that the human appendix is a completely
vestigial organ?

Ichthyosaurs were aquatic dinosaurs. Fossils show us that they had dorsal fins and tails, as do fish, even
though their closest relatives were terrestrial reptiles that had neither dorsal fins nor aquatic tails. The dorsal
fins and tails of ichthyosaurs and fish are

Monkeys of South and Central America have prehensile tails, meaning that their tails can be used to grasp
objects. The tails of African and Asian monkeys are not prehensile. Which discipline is most likely to provide
an evolutionary explanation for how this difference in tails came about?

The nutritional information on a cereal box shows that one serving of a dry cereal has 200 kilocalories. If one
were to burn one serving of the cereal, the amount of heat given off would be sufficient to raise the temperature
of 20 kg of water how many degrees Celsius?

The molecular mass of glucose (C6H12O6) is 180 g. Which of the following procedures should you carry out to
make a 0.5 M solution of glucose?

You have a freshly-prepared 0.1M solution of glucose in water. Each liter of this solution contains how many
glucose molecules?

You have a freshly-prepared 1M solution of glucose in water. You carefully pour out a 100 mL sample of that
solution. How many glucose molecules are included in that 100 mL sample?