1Why do we call dark matter "dark"?
It emits no or very little electromagnetic radiation of any wavelength.
2Based on current evidence, a supercluster is most likely to have formed in regions of space where...?
the density of dark matter was slightly higher than average when the universe was very young
3How are rotation curves of spiral galaxies determined beyond radii where starlight can be detected?
Through observations of the 21cm line of atomic hydrogen
4What is meant by "dark energy"?
the agent causing the universal expansion to accelerate
5When observing a galaxy 100 million light years away, what do we see?
The light from the galaxy as it was a 100 million years ago and it's redshifted.
6If the universe is open...?
Material will get further and further apart, and eventually no new stars will form
7How does gravitational lensing tell us about the mass of a galaxy cluster?
Using Einstein's general theory of relativity, we can calculate the cluster's mass from the precise way in which it distorts the light of galaxies behind it.
8How old is the universe and how do we know?
14 billion years old; the expansion of the universe appears to have started about this long ago
9Something about Omega M (the Q looking shit with an M exponent)
If it's more than 1, the universe will recollapse; less than 1, the universe will expand forever; and equal to 1, the density of the universe is critical.
10What's NOT an example of dark matter?
The star Sirius A
11Which of the following is not a type of galaxy?
Ir
12Population I stars are...?
Found mainly in the outer regions of galaxies and are younger and more blue than other stars
13Deuterium is formed by the combination of...?
A proton and a neutron
14What's not a part of the Big Bang Nucleosynthesis? (formation of elements heavier than Hydrogen isotopes)
The fusion of a neutron with 4He to create 5He
15What's correct about the Big Bang Theory?
75% of the mass of baryonic matter ended up in Hydrogen, with about 25% in Helium; about 380,000 years after the BB, radiation decoupled from matter and the universe had a temperature of about 3,000 K; and that temperature drops as the Universe expands.
16What's NOT true about the Cosmic Microwave Background?
It was first discovered by Penzias and Wilson in the 1940s (actually the 60s)
17What's the timeline of the Universe?
Big Bang, Dark Ages, Reionization
18What best describes the epoch of reionization?
High energy light, produced by early stars and galaxies, hit atoms and removed electrons from them, making the universe transparent.
19What's the chronological formation of stars?
Cold molecular gas, gravitational collapse, formation of disk, and protostar phase.
20Cosmic Dawn...?
refers to the era of reionization, was caused by the birth of young stars that produced UV photons, occurred 500M years after the Big Bang, and lasted for 500-600 million years
21What does the theory of inflation say?
Space underwent a rapid expansion in a very brief period in the early universe.
22The age of the universe is...?
14 billion yrs
23What force is NOT described by the standard model?
Gravity
24What fundamental force keeps atomic nuclei from falling apart?
Strong nuclear force
25How do two electrons react?
Through the electromagnetic force
26What is NOT a conservation law?
Conservation of entropy
27Electrons and positrons collide and produce...?
Photons
28What's NOT correct about entropy?
The entropy of a system is an invariant quantity over time
29The curvature of the Universe is...?
Flat
30How many quarks do electrons have?
NONE. THEY DON'T HAVE ANY. Only neutrons and protons have quarks.
31What happens when anti-matter and matter interact with each other?
They annihilate each other, resulting in the conversion of matter to energy
32What made Darwin's work on evolution so unique and convincing?
The volume and strength of the data and using scientific methods to understand the data.
33Who was the first to explain by mathematical methods the universal laws governing the motion of planets?
Kepler
34What was the experimental confirmation for predictions of the general relativity?
The precession of the perihelion of Mercury
35What observations by Galileo rejected the Aristotelian geocentric model of the universe?
Observing the four moons of Jupiter
36What do high mass stars mostly make?
Supernovae
37What do low mass stars mostly make?
White dwarfs
38When the gas around a black hole spirals inwards, what does the black hole emit?
X-rays
39How big is a white dwarf's radius?
Very large (7000kms)
40What is escape velocity?
The minimum speed needed for a free object to escape from the gravitational influence of a massive object.
41What is the composition of the gas between stars?
98% Hydrogen and Helium, 2% heavier elements
42What happens after the hydrogen-burning phase in a low mass star?
The core collapses
43What's not a stage in the evolution of a massive star?
Black Dwarf
44Where can elements heavier than carbon be produced?
In the core of massive stars
45What's the main source of heat and light from stars?
Nuclear reaction
46Where have elements heavier than iron been produced in?
Supernovae
47Is the minimum temperature for Carbon fusion higher or lower than Helium fusion? Do heavier elements require higher or lower temperature to start a fusion?
Higher, Higher
48What is the result of oceanic divergence?
New seafloor is created.
49What DIDN'T help our Earth develop and retain its atmosphere?
Being so close to the sun, such that the gas atoms making up our atmosphere kept a high thermal velocity.
50What tectonic plate motion is responsible for the formation of deep-sea trenches, like the Marianas Trench?
Ocean-Ocean convergence
51Why does the moon appear to be covered in impact craters butthe earth doesn’t
Earth was hit just as much as the moon, but volcanic activity and erosion slowly erased the craters
52What supports the idea that Mars once had water?
Layers of sedimentary rock, deep canyons, and sulfide materials.
53What is NOT a reason why the terrestrial planets are largely devoid of light elements like Hydrogen and Helium, compared to Gas Giants?
The initial gas cloud which formed the sun and planets was already devoid of the light elements in that specific region.
54What is the name of the technique for finding exoplanets by looking for the shift in spectral lines caused by a star's motions?
Doppler Technique
55What is it called when dense materials sink towards the center of a planet while lighter material move towards the surface when planets develop?
Differentiation
56Around 4.5 billion years ago, the early Earth experienced a catastrophic impact. What was produced by this event?
The moon was formed.
57Which planets are terrestrial planets?
Mercury, Venus, Earth, Mars
58Without greenhouse gases like carbon monoxide, what would happen to the temperature of the Earth?
It would decrease.
59Which part of the electromagnetic spectrum is least absorbed by greenhouse gases and the atmosphere?
Visible
60Oxygen in the atmosphere does NOT...
Make up 50% of Earth's atmosphere. IT DOES NOT.
61What allowed living organisms to move from the sea to the land?
Formation of the ozone layer.
62What is true about photosynthesis in plants?
It is largely responsible for oxygen and carbon dioxide levels in the atmosphere, and both water and sunlight are necessary reactants for it to occur.
63What does the "assumption of mediocrity" imply?
The initial conditions needed to kickstart life are not special.
64Why is Pluto a bad place to look for life in our Solar System?
It's too cold and has no liquid water.
65What event caused the extinction of dinosaurs approx. 65 million years ago?
A large meteor crashed into Earth where is now the Gulf of Mexico.
66What is the habitable zone around a star?
The range of distances from a star that can support water in liquid form.
67What can be used to reveal the various stages of Earth's history?
Rock Layers, Fossils, and Elemental Abundances
68Which cells have qualities of both Prokaryotes and Eukaryotes?
Archaean cells.
69What is the process of endosymbiosis?
The combination of two simple prokaryotic cells to produce one eukaryotic cell.
70What is the primary difference between prokaryotes and eukaryotes?
Eukaryotes have a nucleus; prokaryotes don't.
71What is true about adenosine triphosphate (ATP)?
It's known as the energy currency of a cell, it's a high-energy molecule due to the presence of the last two unstable phosphate bonds, and it's composed of adenine, ribose, and three phosphates.
In order to have a stabilized structure of lipid molecules, a two-layered structure called a lipid
72bilayer is required. Which of the following best describes this structure?
The two layers are oriented in opposite directions, with the hydrophilic heads of fatty acids faced towards the edges of the structure while the hydrophobic tails face towards the interior.
73What best describes Ribonucleic acid (RNA)?
It's a messenger molecule which takes instructions from DNA and uses them to direct the production of proteins.
74What is NOT true regarding DNA and RNA?
That they both have a double-stranded structure, forming a helix shape. They DON'T.
75What's true about carbon's versatility and its ability to form millions of molecules, the basis for organic chemistry?
A carbon atom can simultaneously make four covalent bonds, carbon bonds have the ability to rotate freely, and varying the spatial structure of its atomic bonds results in the formation of different isomers.
76What is the smallest unit of life?
THE CELL, BABY!
77What's NOT true regarding proteins?
They are found only in muscular tissue, helping in functions such as muscle contraction and the helping of the heart to pump blood. PROTEINS DON'T DO ANY OF THIS.
78What are the properties of water that make it essential for life on Earth?
It has a high heat capacity, has cohesive and adhesive properties, and has a polar solvent nature that facilitates chemical reactions.
79What are organic molecules mostly made of?
Carbon and Hydrogen
80What element is the main basis for life on Earth?
Carbon
81What type of chemical bond occurs when one electron is transferred between the outermost shells of two atoms, making each of those shells complete?
Ionic bond
82What is the name of the shell of an atom that dictates its chemical properties via number of electrons?
The valence shell