What is the Astronomical Unit (AU)?
It is the average distance between the Earth and the Sun.
b. It is the radius of the Solar System.
It is the average distance between two galaxies.
It is the distance between the Earth and the Moon.
Which of the following correctly gives the Earth's cosmic address?
Earth, Moon, Solar System, Local Group, Milky Way Galaxy, Local Super Cluster.
b. Earth, Solar System, Local Super Cluster, Local Group, Milky Way Galaxy.
Earth, Milky Way Galaxy, Local Group, Local Super Cluster, Solar System.
Earth, Solar System, Milky Way Galaxy, Local Group, Local Super Cluster.
Which one has the correct order in levels of biological organization from the smallest to the largest scales?
Atom, Molecule, Cell, Organ System, Organ, Organism.
Cell, Tissue, Organ, Organ System, Organism, Population.
Community, Population, Organism, Organ, Tissue, Cell.
Molecule, Cell, Organ, Population, Ecosystem, Biosphere, Organism
What is the speed of light?
300 (km/s)
300,000 (km/s)
300,000 (m/s)
300 (m/s)
The color of light is determined by its:
Speed
Amplitude
Wavelength
brightness
Light from distant objects seems:
very dim because brightness decreases as the square of the distance from the source increases.
very bright because distant sources are brighter in nature.
very dim because photons lose energy as they travel.
very bright because brightness increases as the square of the distance from the source increases.
What happens to the brightness of a light source if we double its distance from us?
It will be doubled.
It will be halved
It looks 4 times fainter.
It looks 4 times brighter
The number of ___ in the nucleus of an atom determines what element a substance is.
Electrons
Protons
Photons
Neutrons
When an electron drops from a higher orbital to a lower one:
A photon with the same orbital energy difference is absorbed.
A photon with less orbital energy difference is absorbed.
A photon with less orbital energy difference is emitted
A photon with the same orbital energy difference is emitted.
The higher the frequency of an electromagnetic wave:
The longer the wavelength.
The higher the speed.
The shorter the wavelength.
The lower the speed.
Red light has a ___ frequency, ___ energy and ___ wavelength than blue light.
higher, higher, shorter
lower, lower, longer
higher, lower, shorter
lower, higher, longer
Which of the following is sorted in order of increasing energy?
Gamma ray, X-ray, UV, Visible, IR, Radio
Microwave, Radio, UV, Visible, X-ray, Gamma ray
Radio, Microwave, IR, Visible, UV, X-ray
Radio, UV, Microwave, Visible, X-ray, Gamma ray
Which physical quantity describes how fast atoms bounce around in an object?
Temperature
Volume
Mass
Density
A cloud of cool, low-density gas in front of a hot source of thermal radiation produces a/an:
Emission-line spectrum
Absorption-line spectrum
Continuous spectrum
Thermal radiation spectrum
All distant galaxies are moving away from us. What does this observational fact tell us about the light of far away galaxies?
The light gets blueshifted (The wavelength becomes shorter).
The light gets redshifted (The wavelength becomes longer).
There is no change in the wavelength of light.
Depending on the type of galaxy, it either gets redshifted or blueshifted.
The amount of energy radiated per second from each square meter of a thermal radiator strongly depends on...(Remember the Stephan-Boltzmann law)
Type of the object.
The mass and size of the object.
The temperature of the object.
The temperature and size of the object.
A piece of hot steel bar emits:
No radiation at all.
Emission-line radiation.
Absorption-line radiation.
Thermal (blackbody) radiation.
What happens when we cool off an object?
It starts to emit thermal radiation more strongly at longer wavelengths.
It starts to emit thermal radiation more strongly at shorter wavelengths.
It always stops emitting the.rmal radiation
Since its temperature drops, it starts to emit emission-line radiation.
According to Bohr's atomic model, what happens when an electron falls from an upper energy level to a lower energy level?
It absorbs some energy equivalent to the energy difference of levels.
It emits some energy in form of a photon with an energy equal to the energy difference of levels.
It always swaps its energy level with another electron in an upper energy level without absorbing or emitting any photons.
It emits a continuous spectrum of photons with a variety of energies.
The farther a galaxy is, the faster it is moving away from us. This was an observation made by:
Stefan-Boltzmann
Edwin Hubble
Albert Einstein
Heinrich Olbers
The cosmological principle states that:
We are the center of the Universe because all galaxies are moving away from us
We are not the center of the Milky Way because we our solar system is orbiting the central black hole.
We are not the center of the Universe because space is expanding in all directions, giving the appearance that we are at the center.
We are not the center of the Universe because space is expanding in all directions, giving the appearance that we are at the center. d.
What happens to light waves as it is traveling through empty space (no gas or dust in the way)?
It loses energy as time passes
It contracts since the space it is traveling in is shrinking
It stretches since the space it is traveling in is expanding
It continues to travel in empty space without incident
What is one main conclusion of Hubble’s Law?
The universe is not expanding and is in fact getting smaller.
. The universe is actually neither expanding nor shrinking.
Galaxies farther away from us are moving closer to us at higher velocities.
Galaxies farther away from us are moving away from us at higher velocities
If you take the inverse of Hubble’s constant, then what does that tell you about the universe?
Age
Expansion Rate of Space
How did the Universe become transparent?
Electrons and ions cooled off and recombined to form atoms, allowing light to pass.
Electron and ions got hotter causing the atoms to never form, allowing light to pass.
Photons never allowed Hydrogen atoms to form as they continuously ionized them.
The universe is not transparent, but opaque. The light is constantly absorbed and never re-emitted.
What happens when anti-matter and matter interact with each other?
They pass through each other
They annihilate each other, resulting in the conversion of matter to energy.
They merge with each other to form a new particle.
They annihilate each other, resulting in the loss of energy
Which one of the following are the four fundamental forces in the universe?
Gravity, Electromagnetism, Strong, GUT
Gravity, Electroweak, Strong, Weak
Gravity, Electroweak, Small, Large
. Gravity, Electromagnetism, Strong, Weak
The theory of inflation says that:
Space underwent a rapid expansion in a very brief period in the early universe
Space underwent a rapid compression in a very brief period in the early universe
Space underwent a slow expansion in a very long period in the early universe
Space underwent a slow compression in a very long period in the early universe
How did the theory of inflation solve the flatness problem?
Because of the rapid compression of space, the Universe had its curvature flattened.
Because of the slow expansion of space, the Universe had its curvature flattened
It doesn’t solve the flatness problem.
Because of the rapid expansion of space, the Universe had its curvature flattened.
Which statement is correct about the big bang theory?
It predicts that about 75% of the mass of the baryonic matter ended up in Hydrogen, with about 25% in He.
It predicts that about 380,000 years after the big bang, radiation decoupled from matter and this radiation is now observed as the CMB with a current temperature of about 3 Kelvin
It predicts that temperature drops as the Universe expands.
All of the above.
The initial matter perturbations which grew with time and later formed galaxies and clusters of galaxies are observationally imprinted in the:
Cosmic Microwave Background(CMB) radiation
Nuclei of H and He
Planck Era
All of the above
How long after the Big Bang was the CMB formed?
1 second
380,000 years
100,000,000 years
10-33 seconds
How do the temperature and matter density of the Universe change with time?
They both increase with time
They both decrease with time
Matter density decreases but temperature increases
Matter density increases but temperature decreases
The curvature of the universe is:
Flat
Open
Closed
Twisted
If the density of the universe is than the critical density, then it will ____. If the density of the universe is than the critical density, then it will ____.
greater, expand, less, collapse
less, expand, greater, stay the same
less, expand, greater, collapse
less, stay the same, greater, expand
The fate of the universe is controlled by:
energy of expansion
gravitational energy
binding energy
The universe is made up of:
73% Dark Matter, 23% Dark Energy, and 4% Atoms
73% Atoms, 23% Dark Matter, and 4% Dark Energy
73% Dark Energy, 23% Dark Matter, and 4% Atoms
73% Dark Energy, 23% Atoms, and 4% Dark Matter
The Big Crunch is a cosmological scenario that says the future of our universe is:
The universe will stop expanding and collapse on itself.
The universe will stop expanding and stay the same.
The universe will expand faster and faster.
The universe will stop expanding and then expand even faster
The bending and magnifying of light due to gravity is known as:
the cosmological principle
Olbers’ Paradox
Gravitational Lensing
Hubble’s Law
Where do stars mostly form?
In very hot gases rich in Hydrogen atom
In very hot gases at the center of the galaxies
In cold molecular gases
In the less dense hot gas between galaxies
Which of the following is NOT a feature of the elliptical galaxies?
They have no particular shape
They have no spiral arms
They have smooth featureless appearance
They have old stellar population
What is the Hubble’s tuning fork?
It is used to tune musical instruments
It is a tuning fork shaped diagram into which galaxies are organized morphologically
It is a way to classify stars within a galaxy
It is the formation model of the Universe
Which of the following is correct about the irregular galaxies?
They have many hot, young stars
They have spiral arms
They have large amounts of interstellar matter
They have many hot, young stars & They have large amounts of interstellar matter
Largest galaxies in rich clusters reside close to the ...
cluster's disk
cluster's halo
cluster's center
cluster's edge
In rich clusters most galaxies are in the form of ... and ...
Spiral, Elliptical
Elliptical, S0
Irregular, Elliptical
Irregular, Spiral
Most galaxies that are not in clusters are in the form of ... and ...
Which statement is NOT true about rich clusters of galaxies?
Rich clusters contain hundreds to thousands of member galaxies.
Rich clusters have hot gas and dust
Rich clusters have a ragged, irregular appearance
Rich clusters are roughly spherical
What seems to be playing an important role in keeping galaxy clusters together, is the ...
Dark Energy
Electron Degeneracy pressure
Dark Matter
Dark Chocolate
The Metallicity (Fraction of heavy elements) of the Inter Galactic Medium is usually ... that of the Interstellar Medium.
Less than
higher than
equal to
twice
What process forms new elements in stars?
Fission
Fusion
Nucleosynthesis
photosynthesis
What will finally happen to the Sun?
It will explode in a supernova explosion.
It gradually ejects its outer layers to later form a planetary nebula and its leftover core turns into a white dwarf.
It finally turns into a black hole surrounded by a planetary nebula.
It becomes a rotating neutron star that regularly emits pulses of radiation.
What is the maximum mass that a stable white dwarf star can have (The Chandrasekhar mass limit)?
1.4 times the mass of the Sun.
3 times the mass of the Sun.
100 times the mass of the Sun.
0.1 times the mass of the Sun.
What is the main source of energy in the Sun?
Nuclear fission in the core.
Nuclear fusion in the core.
Gravitational contraction of the Sun.
Magnetic field of the Sun.
How do very massive stars die eventually?
They explode in a supernova explosion and leave a neutron star or a black hole behind.
They turn into a planetary nebula.
They explode in a supernova explosion and leave a white dwarf star behind.
Very massive stars never die. They keep on producing energy forever.
What is the heaviest nucleus that can be formed in the core of very massive stars?
Uranium.
Carbon.
Helium.
Iron.
Very heavy elements such as uranium, gold and mercury are formed in ...?
The Big Bang.
The core of low-mass stars.
The core of high-mass stars.
Supernova explosions
Astronomers use supernovae type Ia to directly measure ...?
The speed of light in distant galaxies.
Temperature of nearby galaxies.
Distance to faraway galaxies .
Rotation curve of the Milky Way galaxy.
Which of the following describe the early stages in the formation of stars in the right order?
Cold molecular gas, Gravitational collapse, formation of disk, protostar phase
Hot molecular gas, Gravitational collapse, formation of disk, protostar phase
Protostar phase, hot molecular gas, gravitational collapse, formation of disk
Cold molecular gas, protostar phase, gravitational collapse, formation of disk
Why is it difficult to find protostars using optical telescopes?
Because protostars do not exist in the nearby Universe
Because protostars are shrouded by gas and dust
Because protostars are black
Because protostars are much smaller than the smallest planets
What is the composition of the gas between stars?
It is all made of Hydrogen and Helium
98% Hydrogen and Helium and 2% heavier elements
50% Hydrogen and 50% Helium
It is mostly made of metals
Why don't we have any star less massive than 0.08 times the mass of the Sun?
Because gravity is not strong enough to cool down the gas at the center of these objects
Because all of these objects explode before being able to form a star
Because gravity is so strong in these objects that prevents the formation of a star
Because their cores never reach hydrogen fusion temperatures
What is the Hertzsprung-Russell (H-R) diagram?
It is a plot of luminosity versus temperature where stars are located
It is a plot of chemical composition of the stars
It is a plot of luminosity versus number of stars
It is a plot of mass versus chemical composition
What mechanism prevents stars of mass less than 0.08 times the mass of the Sun from collapsing under the influence of gravity?
Radiation pressure
Degeneracy pressure
Osmotic pressure
Peer pressure
What element is produced in the final stages of fusion inside a star similar to the Sun?
Helium
Carbon
Hydrogen
What is the definition of half-life for materials that undergo radioactive decay?
It is the time it takes for the atoms of the material to disappear completely
It is the time it takes for half of the atoms in a given sample of the material to decay
It is the time since the big bang for all radioactive materials
It is the time it takes for 80 percent of the atoms of the material to decay
What is radioactive dating used for?
To measure the distance to objects
To measure the temperature of material
To measure the age of material
To measure the metallicity of material
Which of the following should be among the predictions of any model of the solar system’s formation?
Rocky, dense planets must be found close to the sun
Planets must go around the sun in more or less the same plane
There should exist a lot of gas and dust in inner parts of the solar system close to the sun
Rocky, dense planets must be found close to the sun & Planets must go around the sun in more or less the same plane
Which of the following is the most successful model of solar system formation?
Solar Nebula Theory
Collision with another star Theory
Dark Matter Theory
Big bang Theory
One explanation of why the planets near the Sun are composed mainly of rock and iron is that ...?
The Sun’s magnetic field attracted all the iron in the young Solar System into the region around the Sun
The Sun is made mostly of iron, so gas ejected from its surface cooled and condensed to form iron rich planets
The Sun’s heat made it difficult for other substances such as ices and gases to condense near it
The Sun’s gravity pulled iron and other heavy material inward and allowed the lighter material to float outward
What was the separation process in the formation of planets during which denser material sank toward the center of bodies and lighter material floated toward the surface?
Integration
Differentiation
Materialization
Globalization
What are the two main processes that could have formed the atmosphere of planets?
Condensation and Outgassing
Outgassing and Collisions
Melting and Collisions
Vaporization and Melting
Why is it difficult for smaller planets to form an atmosphere?
Because smaller planets do not get hot enough to have an atmosphere
Because smaller planets have a different chemical composition not allowing them to have an atmosphere
Because small planets have weak gravity that makes it difficult for them to hold on to the atmospheres they form
Because smaller planets form at much earlier stages in the formation of Solar System
What are the main methods for detecting extra solar planets (Exoplanets)?
Doppler Method, transit method and gravitational lensing
Gravitational lensing, laser method and Doppler method
Doppler method, transit method and Dark Matter method
Transit method, Doppler method and laser method
How do we detect planets using the transit method?
By looking at the blue shifting and red shifting of light
By looking at the change in brightness as the planet moves in its orbit around the star
By looking at the gravitational effects of the star on planet
By looking at the direct images taken from the planet
What parameters determine the environment of a planet?
Mass and size of the planet.
The role of atmosphere.
The role of sunlight.
Which statement is NOT correct about outer planets in the solar system?
They have many moons.
They are mostly made up of rocks and metals.
They are bigger and more massive than inner planets.
They have no solid surface.
The Earth's crust is mostly made up of ...?
Oxygen and hydrogen.
Hydrogen and helium.
Oxygen and silicon.
Iron and nickel.
In which layer of the Earth's interior, heat is mainly transported to upper layers by convection?
The crust.
The mantle.
The solid inner core.
Crust and solid inner core.
Earthquakes and volcanoes on Earth are more active near ...?
Plate boundaries.
Bottom of the oceans.
Continents.
The Earth's core.
What is the main source of the Earth's magnetic field?
Solar flares.
Current flows in the molten iron core.
Iron content of the Earth's crust.
Motion of charged particles in the atmosphere.
Where is the the ''frost line'' (the division between the inner warm part and outer cold parts of the solar system) located?
between the orbits of Saturn and Neptine
between the orbits of the Earth and Venus
between the orbits of Earth and Mars
between the orbits of Mars and Jupiter.
What is believed to be the origin of Earth's Moon?
A catastrophic impact with a Mars-sized object 4.5 billion years ago
Orbital capture of a passing celestial body
Aliens put it there
It formed the same time Earth had formed.
Which statement is correct?
There was liquid water on the Earth’s surface 4.5 billion years ago.
There is more CO2 in the atmosphere than in the oceans now.
There is more Oxygen in the atmosphere now than 4 billion years ago.
Oceans formed on the surface of the Earth two thousand years ago.
What is the origin of Oxygen in the Earth’s atmosphere?
Comets and asteroids
Plants and bacteria
Volcanoes
The Sun
If the thermal velocity of atmospheric gas is ___ the escape velocity of the planet, the atmosphere can escape.
Half of
Much less than
One fourth of
Close to
The Earth’s atmosphere is mostly composed of ___.
Oxygen
Nitrogen
Methane
The higher the elevation on Earth, ___ the atmospheric pressure.
The same
The higher
The lower
The colder
Which part of the Electromagnetic spectrum is more absorbed by Greenhouse gasses?
Ultraviolet
Radio
Infrared
Gamma rays
What is some evidence supporting that all continents were once united into one single continent?
Distinctive fossil groups found in Africa and South America
Similarities of geological features and rock ages on opposite sides of the Atlantic Ocean
Similarities in shorelines
Why was the continental drift hypothesis rejected at the time of proposal?
Similarities of fossils on both sides of the Atlantic Ocean
Inadequate mechanism of continental movement
Similarities of rock ages in some continents
Continental shoreline similarities
Which of the following supports the “seafloor spreading” hypothesis?
Seafloor is younger near the ridges
The ages of the seafloor are symmetric on either side of the ridges
Magnetic polarity reversals are recorded in ocean floor
What mainly causes the Earth’s crust to be dynamically moving?
Convectional currents in the mantle
Tidal forces on the Earth’s crust
Earthquakes and volcanoes
Meteorite impacts
The Mid-Atlantic ridge is a result of ___?
Transform faults
Convergent plate boundaries
Divergent plate boundaries
Side-to-side plate boundaries
Subduction of oceanic plates and formation of volcanic mountains, accompanied by earthquakes is a result of ___?
In ___, the continental lithosphere cannot recycle. The crust thickens creating high mountains, a wide plateau, and severe earthquakes.
Continent-continent convergence
Ocean-continent convergence
Ocean-ocean convergence
Ocean-ocean divergence
Which of the following correctly describes the geological time scales in order of increasing divisions of time?
Eon, Era, Period, Epoch
Period, Epoch, Era, Eon
Epoch, Period, Era, Eon
Era, Eon, Period, Epoch
Which of the following is NOT true about the early Earth?
Violent impacts were fairly common.
Early Earth was relatively cool.
Earth was very hot at the beginning.
Heavier elements sank to the center and lighter elements moved toward the surface.
The correct description of the Earth’s layers from inside out is given in which of the following choices?
Liquid iron inner core, solid iron outer core, mantle, crust
Mantle, crust, solid iron inner core, liquid iron outer core
Liquid iron outer core, solid iron inner core, mantle, crust
Solid inner iron core, liquid outer iron core, mantle, crust
What is believed to be the reason for the late Heavy Bombardment between 4 to 3.8 billion years ago?
Change in the orbits of the Jovian planets.
Change in the temperature of the Sun
Complete reversal of the orbits of planets due to a nearby star.
Change in the chemical composition of the Sun.
When the Earth formed and the crust first cooled and solidified, what was the dominant rock type?
Igneous rock
Metamorphic rock
Sedimentary rock
Both a and b
What is the most common rock type on the Earth today?
Which of the following are possible causes for mass extinctions?
Massive meteor impact
Global rise or fall in the Earth’s temperature
Increased global volcanic activity
Ozone layer in the atmosphere blocks which part of the Sun’s light spectrum more?
Gamma ray
Visible
When did oxygen start building up in the Earth’s atmosphere?
When the Earth was forming.
When the Earth was half its present age.
When dinosaurs became extinct.
When the Universe was half its present age.
Why is there less CO2 in the atmosphere in the summer months, compared to the winter months?
People greatly decrease their CO2 emissions in the summer.
The Earth is farther away from the Sun in the summer.
There is more direct sunlight in the summer.
Many plants die in the winter, so there are more plants that are photosynthesizing in the summer.
The smallest unit of life that can function independently and perform all the necessary functions of life is ___.
An organ
A cell
An atom
A tissue
A/An ___ cell has a central control structure called a nucleus, which contains the cell’s DNA.
Prokaryotic
Archaean
Viral
Eukaryotic
Different independent parts of a eukaryotic cell that are assigned different functions are called ___.
Organs
Nuclei
Organelles
DNAs
What is correct about plant and animal cells?
Animal cells have mitochondria, while plant cells have both mitochondria and chloroplasts.
Plant cells have mitochondria, while animal cells have both mitochondria and chloroplasts.
Animal and plant cells have chloroplasts.
Animal and plant cells lack chloroplasts.
Mitochondria are able to metabolize ___.
Phosphorus in the presence of oxygen.
Sugar in the presence of oxygen.
Sugar in the presence of sunlight.
Sugar in the presence of both sunlight and oxygen.
According to Endosymbiosis Theory, Eukaryotic cells are formed by:
The folding of a membrane or tissue.
The combination of two or more prokaryotic cells.
The division of a bigger cell into smaller eukaryotic cells.
Plant cells.
Which of the following is a common characteristic of life?
Growth
Metabolism
Reproduction
Living things are made up of ___ amino acids.
Left-handed
Right-handed
Both left and right-handed
Neither left nor right-handed
What are the two main varieties of nucleic acids?
DNA and RNA
Sugars and lipids
Lipids and carbohydrates
Lipids and steroids
Which of the following is a genetic material that stores information for their own replication and for the sequence of amino acids in proteins?
RNA
Phospholipids
DNA
Monosaccharaides
DNA bases are connected with ___?
Metallic bonds
Covalent bonds
Hydrogen bonds
Ionic bonds
What element is the main basis for life on Earth?
Water
Silicon
Three main types of cells are _____:
Prokaryotic, Eukaryotic, and Archaean.
Bacterias, Archaeas, and Prokaryotic.
Bacterias, Archaeas, and Animal.
Animal, Plant, and Prokaryotic.
These types of cells have qualities of both Prokaryotes and Eukaryotes:
Archaean Cells
Viral Cells
Bacterias
Plant Cells
The main kingdoms of eukaryotic cells are:
Bacteria and Archaea
Plantae, Animalia, Fungi, and Protista
Bacteria, Archaea, and Protista
Bacteria, Archaea, Animalia, and Fungi
______ cells are usually found in harsh environments and may use inorganic chemicals to generate energy.
Bacterial
Animal
How many types of amino acids are used by life on Earth?
3
10
20
25
Adenosine triphosphate (ATP) is used by cells for what purpose?
Regulating osmosis
Storing energy
Managing the expression of DNA
Communicating with other cells
How do the structures of DNA and RNA compare?
both DNA and RNA are double-helix shaped
DNA is double-helix shaped while RNA is single-stranded
RNA is double-helix shaped while DNA is single-stranded
both DNA and RNA are single-stranded
What aspect of a DNA molecule is responsible for encoding information?
the sugar-phosphate backbone
the nitrogenous base pairs
the secondary structure
the tertiary structure
Proteins are built from long chains of which molecules?
Carbohydrates
Lipids
Amino Acids
Water molecules
What nucleotides are found in DNA?
Cytosine, thymine, adenine, guanine
Cytosine, uracil, adenine, guanine
Thymine, adenine, guanine
Cytosine and guanine
What property or properties of water make it essential for life on Earth?
its cohesive and adhesive properties
a high heat capacity
its polar solvent nature, facilitating chemical reactions
all of these answers