UPDATED ACTUAL Exam Questions and
CORRECT Answers
Think of the concept of deep time. How would you describe the distribution of events over time?
Are they evenly distributed? If not, how then? - CORRECT ANSWER - There is an
uneven distribution of life formation on Earth if you look at it from a yearly scale. From the
formation of the Earth to the introduction of algae, everything was pretty evenly spaced;
however, following the ice age, there is an exponential growth of life forms within a very short
period of time
According to scientific evidence, approximately how long ago did Earth form? - CORRECT
ANSWER - 4.6 billion years ago
For how long did Dinosaurs roam on Earth? - CORRECT ANSWER - approximately 165
million years
There are limits the usefulness of diffusion in biological processes. What limitations can you
think of? - CORRECT ANSWER - Diffusion, though typically consistent, has patterns that
don't follow specific rules. For example, in the pattern of high concentrations moving to low
concentrations, not every particle will use that specific method. Additionally, the limits of space
and time occur as it will take a much more significant amount of time for diffusion to occur in
spaces that are over what is normally seen in a typical rate.
How does random movement of individual particles result in predictable movement form high to
low concentrations? Explain in 3-4 sentences. Come up with your own words: don't copy your
notes. - CORRECT ANSWER - Although an individual particle does not follow a specific
movement, the likelihood that some or most particles will end up crossing from high to low
concentrations during their diffusion allows us to recognize an overall pattern. If you watch a
specific particle, it is likely, but not guaranteed, that it will move from high to low.
Why is it important, in this context, to distinguish between Oxygen and O2? - CORRECT
ANSWER - Oxygen and dioxygen differ in their chemical bonds but also have differences
,when it comes to the impact which they hold. Oxygen forms dioxygen which makes up the air
we breathe.
When did O2 first appear in the atmosphere, both in years, and after which event? - CORRECT
ANSWER - O2 first appeared 3000 mya following the development of the first land
masses appeared on Earth.
Explain why oxygen levels stayed constant for over one billion years at a relatively low level. -
CORRECT ANSWER - Oxygen levels stayed consistent before the development of
eukaryotes, starting with cyanobacteria. Later, algae chloroplasts developed which began the
process of photosynthesis that impacted the earth's oxygen levels.
What does this sentence mean: "60% of Earth's minerals are biogenic (i.e. generated by life)"? -
CORRECT ANSWER - It means that they formed after O2 appeared in the atmosphere
and ocean. Life on Earth caused a dramatic change in oxygen levels as a result of photosynthesis,
meaning that any mineral formed with oxygen was due to the rise in plant life.
Aside from insect size, what other variables did Clapham and Karr measure? - CORRECT
ANSWER - They measured the size of insect predators, such as birds during these time
periods. They used this data to introduce the idea that insect size was more closely related to
predatorial size rather than high oxygen levels, due to the fact that insect sizes were shrinking
during some of the highest rises in oxygen.
Suppose you discovered a new form of energy. How would you decide whether it should be
categorized as kinetic vs potential energy? - CORRECT ANSWER - Kinetic energy is the
energy of movement. If the form includes any sort of heat, light, or electricity, then it can be
classified as kinetic.
Potential energy is energy that is stored. This includes chemical energy, which is a bond of 4
hydrogen and 1 carbon atom. If this is the chemical makeup, then the energy is potential.
Describe the relationship between the wavelength of energy and the amount of energy it carries. -
CORRECT ANSWER - Shorter wavelengths are an increase in energy as they have more
"bags" of energy photons. Longer wavelengths are a decrease in energy, there is a longer space
between peaks meaning that there are less "bags" crossing a spectrum in the same amount of
time that a shorter wavelength would.
,Describe the three things that can happen to light when it strikes a surface. - CORRECT
ANSWER - Light can be reflected, transmitted, or absorbed.
Given what you learned about light and chlorophyll this week, why do most plants appear green
to us? - CORRECT ANSWER - We perceive plants as green because chlorophyll is
absorbing violet, red, and blue light while reflecting the wavelengths that we see as green light.
What wavelengths (=colors) of light do most plants use as their primary source of energy in
photosynthesis? - CORRECT ANSWER - Plants use the wavelengths of violet, red, and
blue as their source of energy in photosynthesis.
Describe what happens in the light-dependent reactions. - CORRECT ANSWER - ATP is
synthesized, NADPH is generated, and water is split apart in the process to release oxygen as a
byproduct.
Describe what happens in the light-independent reactions. - CORRECT ANSWER - The E
from ATP and NADPH are used to build glucose, this is commonly referred to as the Calvin
Cycle.
Why do plants perform photosynthesis? - CORRECT ANSWER - Plants perform
photosynthesis to make other molecules in the plant. The glucose produced by photosynthesis
aids in building cellulose which makes up the cell wall. It also makes ATP out of it as needed
which is used for all chemical reactions out of the cell.
Review the definitions for Gene and Allele. What is the difference between them, what is their
relationship? - CORRECT ANSWER - a gene is a segment of dna while an allele is a
different form of that gene
Explain why we have two copies of each gene in our cells. - CORRECT ANSWER - we
have two copies of each gene in our cells because a dna strand has two strands and 2
chromosomes
, Given that we have two copies of each gene, do we also have two different alleles for each gene?
How else would you word the relationship between the two? - CORRECT ANSWER -
because there is two copies of each gene we can have at most two different possible alleles as
these alleles are components of genes
Many lessons about genes imply that for each gene, two alleles exist in the population. Is that so?
If not, how would you describe this relationship? [Note, this question is about populations, not
individuals as the previous one was] - CORRECT ANSWER - there is not necessarily two
alleles for each gene but alleles differ from person to person meaning that although one
individual can have a maximum of two, there are infinitely many different base pairs because
two alleles between dna and individuals will not be the same.
What are the four "steps" (or postulates) of natural selection? Describe them, using a
(hypothetical) example. - CORRECT ANSWER - 1. there is a variety of dolphins. some
are pink and some are blue
2. the offspring are a mix up of pink and blue, and there is a pretty even distribution of the two
colors
3. for some reason, the sharks do not like the color pink and tend to either eat or seriously injure
the dolphins who are pink.
4. as a result, there will one day only be blue dolphins since the pink dolphins have specifically
been targeted, making them unable to reproduce.
Think about the definitions of fitness and adaptation. How do these evolutionary definitions
differ from the everyday use of these words? How can this be misleading? - CORRECT
ANSWER - fitness regards a living thing's ability to survive and reproduce in an
environment adaptation whereas to us fitness means the general health of a person. adaptation is
the trait that increases fitness and is produced by natural selection, it is not a sensory adaptation
like we as humans have where our pupils become smaller in bright light.
Think of the definition of fitness - how could you measure the fitness of an individual? -
CORRECT ANSWER - you could measure the fitness of an individual by determining
how well they are able to survive and adapt in a new environment, somewhat like the show
survivor