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What are the four types of atoms that make up 96% of all matter found in organisms?
hydrogen, carbon, nitrogen, and oxygen
hydrogen, carbon, oxygen, and sulfur
hydrogen, oxygen, nitrogen, and phosphorus
hydrogen, oxygen, phosphorus, and sulfur
What types of molecules have hydrophilic interactions?
polar
non polar
ionic
polar and ionic
non polar and ionic
all of the above
Why is it that diving bell spiders do not drown when on water?
surface tension
water resists forces that increase it surface area
cohesion
surface tension and cohesion
Which has greater potential energy?
short bonds like that found in a hydroxyl group
strong bonds
long bonds like that found between carbon and hydrogen
weak bonds
short bonds like that found in a hydroxyl group and strong bonds
long bonds like that found between carbon and hydrogen and weak bonds
Organic molecules means...
molecules that contain carbon
octane
molecules that contain water
molecules that contain carbon and octane
How amino acids make up the building blocks of proteins?
10
20
infinite
50
What makes proteins different from one another
hydrophilic interactions
R-groups
amino group
carboxyl group
amino and carboxyl group
Monomers polymerize through...
condensation reactions
hydrolysis
dehydration reactions
condensation and dehydration reactions
What are the three main components of a peptide-bonded backbone?
R-group orientation
Directionality
Flexibility
R-group orientation and flexibility
What is the secondary structure of proteins?
the unique sequence of amino acids
combinations of polypeptides
interactions between residues that are brought together as the chain bends and folds in space
created by the interactions between functional groups
Molecular chaperones do the following...
denatures proteins
facilitate protein folding
recognize unfolded proteins by binding to hydrophobic patches that are not normally exposed
unfolds proteins
denatures proteins and unfolds proteins
facilitate protein folding and recognize unfolded proteins by binding to hydrophobic patches that are not normally exposed
Which of the following describes enzymes?
"lock and key"
catalyze reactions
none of the above
Fischer's model
Which of the following describes the sugar present in a nucleotide?
4' carbon sugar
6' carbon sugar
5' carbon sugar
Which of the following are pyrimidines?
cytosine
uracil
adenine
guanine
cytosine and uracil
adenine and cytosine
Which term describes the bond that polymerizes nucleic acids?
glycosidic linkages
peptide bonds
phosphodiester bonds
Which of the following is not true of DNA?
tertiary structure follows the Watson-Crick pairing
has ribose as its sugar
has an antiparallel structure
Which term describes this picture?
polypeptide
DNA
RNA
steroid
Which of the following means "many-sugars?"
monomers
monosaccharides
polysaccharides
oligosaccharides
Which of the following is a ketose?
Which of the following describes the chemical structure of starch?
contains alpha-glucose joined by glycosidic linkages
amylose and amylopectin
both alpha 1,4 glycosidic linkages and alpha 1,6 glycosidic linkages
contains alpha-glucose joined by glycosidic linkages and both alpha 1,4 glycosidic linkages and alpha 1,6 glycosidic linkages
Which of the following describes a glycoprotein?
is a protein that is linked to a carbohydrate
protein that is linked to a oligosaccharides
spans the glycolipid
Highly unsaturated lipids are _____ at room temperature
solid
partially solid
partially liquid
liquid
What is the commonality shared between micelles and lipid bilayers?
They are both circular in formation
They are both linear in formation
Both have hydrophobic tails facing one another
Both have hydrophobic heads facing one another
Lipid bilayer with short and unsaturated hydrocarbon tails have...
lower permeability
lower fluidity
higher permeability
The following statement describes which: As water leaves, the vesicle shrinks and the membrane shrivels.
hypotonic
hypertonic
isotonic
Exergonic reactions have the following qualities...
delta G is less than zero
delta G is greater than zero
delta G is equal to zero
Phosphorylation is when...
addition of a phosphate group to a substrate
removal of a phosphate group to a substrate
The following characteristics represent an "induced fit":
reorients the substrates and bind them tighter to the active site
conformational change of the active site
when substrate and active site collide in precise orientation
reorients the substrates and bind them tighter to the active site and conformational change of the active site
Which of the following describes feedback inhibition?
when the concentration of a product molecule becomes rare
when the concentration of the product molecule becomes abundant
"feeds back" to stop reaction sequence
"feeds back" to stop product sequence
when the concentration of the product molecule becomes abundant and "feeds back" to stop reaction sequence
when the concentration of a product molecule becomes rare and "feeds back" to stop reaction sequence
Which of the following does not occur during glycolysis?
one five-molecule carbon molecule of glucose is broken down
glucose is broken down into two molecules of three-carbon pyruvate
NAD+ is reduced to form NADH
ATP is produced from ADP and Pi
Which of the following is not true about the citric acid cycle?
each acetyl CoA is oxidized to two molecules of CO2
each acetyl CoA is reduced to two molecules of CO2
more ATP and NADH is produced
FAD is reduced to form FADH2
Lactic acid fermentation
regenerates NAD+ by forming lactate
yeast converts pyruvate to the two-carbon compound acetaldehyde
both of the above
Protein conformation is generally not obtained until the
primary level
secondary level
tertiary level
quaternary level
Which of the following hydrocarbons has a double bond in its carbon skeleton?
C3H8
C2H6
C2H4
CH4
Acids in solution
donate OH ions
donate H ions
can remove OH ions
donate OH ions and can remove OH ions
donate H ions and can remove OH ions
The fact that lipids are high in potential energy is due to the
multiple carbon to hydrogen bonds
solubility of each glycerol molecule
the number of oxygen to hydrogen bonds
the number of oxygen to carbon bonds
The amino group can functionally
act as an acid
cause solutions to gain a sour taste
act as a base
none of the above apply
The chemical behavior of amino acids is primarily due to
the nature of the N terminis
the nature of the C terminis
the R group
A triple bond between two atoms would involve the sharing of
2 electrons
3 electrons
8 electrons
6 electrons
The monomers that construct primary proteins are
simple sugars
lipids
amino acids
polypeptides
The atomic number of an atom is 12. The number of valence electrons is
4
3
2
Tertiary structures are more rigid than secondary protein structures because
the number and type of possible chemical bonds increases
the bond length in hydrogen bonds increases
the bond length in hydrogen bonds decreases
the number and type of possible chemical bonds increases and the bond length in hydrogen bonds decreases
none of the above would apply
Most complex carbohydrates are constructed from
glycogen
Enzymes can regulate/influence the amount of energy required for a chemical reaction to proceed
by lowering the activation energy
decreasing the randomness of molecular formation
increasing the randomness of molecular formation
by lowering the activation energy and decreasing the randomness of molecular formation
by lowering the activation energy and increasing the randomness of molecular formation
weak acids typically dissociate
partially
completely
not at all
glycogen is a
monosaccharides stored in animals
monosaccharides stored in plants
polysaccharides stored in animals
polysaccharides stored in plants
the hydrophobic end of a protein would
readily not dissolve in water
readily dissolve in water
make the solution acidic
none of the above is true
if the concentration of H+ ions and OH- ions in solution is equal, then the pH will be
acidic
neutral
basic
strongly acidic
strongly basic
The 5' --> 3' linear directionality of a DNA polymer is established
when the 5' carbon and its phosphate group of a proceeding nucleotide attaches to the 3' carbon of the preceding nucleotide.
only in the anti-parallel strand of DNA
when the nitrogenous bases form hydrogen bonds
none of the above are correct
a pyruvate molecule contains
1 carbon atom
3 carbon atoms
6 carbon atoms
2 carbon atoms
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