Marine Science Final EXAM 2025
QUESTIONS AND ANSWERS
Which of the following conditions is necessary for natural selection to occur? - ANS More
organisms are born than can survive.
The average female cod produces two million eggs in a single spawning; however, only about
200 of the original two million cod survive to age one. When cod reach their reproductive age
of two to four years, only two of the original two million are still alive. What can you conclude
about the traits of the two cod that survived? - ANS These two fish have strong selective
pressure.
In 1989, the Exxon Valdez spilled nearly 42,000,000 liters of oil into Prince William Sound,
Alaska. How would this spill be classified? - ANS Abiotic environmental
Which of the definitions below best defines biomagnification? - ANS A substance that
increases in concentration with trophic level
The following map of the Gulf of Mexico shows reported sightings of whale sharks. What
explanation best describes why the highest reported sightings occur near the mouth of the
Mississippi River? - ANS Whale sharks are filter feeders, and this area is rich in plankton due
to runoff.
Why are shellfish populations often a good indicator of water quality? - ANS Many shellfish
are filter feeders that absorb toxins from the water.
1
Page
@COPYRIGHT BRAINBARTER 2025/2026
, Which statement best describes how pollution can impact the apex predators of the marine
community? - ANS The apex predators are impacted by pollution in the environment
because they are the top of the marine food chain, where accumulation of pollution is quite
great.
A marine biologist explains that the salmon adapts to its environment through descent with
modification. What is "descent with modification"? - ANS A heritable trait can cause one
generation to be slightly different from another.
In the Galapagos islands, larger iguanas are more successful at reproducing and have more
offspring. How would the population change if larger body size also makes iguanas more
vulnerable to predatory birds? - ANS The population would be more balanced between
small, medium, and large body sizes because while larger iguanas reproduce more, smaller
iguanas avoid predators better.
What is overproduction? - ANS The species produces more young than can be supported by
the ecosystem.
What animals would you likely find in this habitat?
swamp with lots of trees - ANS Juvenile fish and shrimp
What prediction can be made about how the distribution of coral reef populations would be
affected if the oceans in which they live were to experience significantly more cloudiness of the
water? he coral population would decrease due to lack of sunlight. - ANS The coral
population would decrease due to lack of sunlight.
The average female Atlantic cod (Gadus morhua) produces two million eggs in a single
spawning. How does this relate to natural selection? - ANS More organisms are born than
can survive.
2
Page
@COPYRIGHT BRAINBARTER 2025/2026
QUESTIONS AND ANSWERS
Which of the following conditions is necessary for natural selection to occur? - ANS More
organisms are born than can survive.
The average female cod produces two million eggs in a single spawning; however, only about
200 of the original two million cod survive to age one. When cod reach their reproductive age
of two to four years, only two of the original two million are still alive. What can you conclude
about the traits of the two cod that survived? - ANS These two fish have strong selective
pressure.
In 1989, the Exxon Valdez spilled nearly 42,000,000 liters of oil into Prince William Sound,
Alaska. How would this spill be classified? - ANS Abiotic environmental
Which of the definitions below best defines biomagnification? - ANS A substance that
increases in concentration with trophic level
The following map of the Gulf of Mexico shows reported sightings of whale sharks. What
explanation best describes why the highest reported sightings occur near the mouth of the
Mississippi River? - ANS Whale sharks are filter feeders, and this area is rich in plankton due
to runoff.
Why are shellfish populations often a good indicator of water quality? - ANS Many shellfish
are filter feeders that absorb toxins from the water.
1
Page
@COPYRIGHT BRAINBARTER 2025/2026
, Which statement best describes how pollution can impact the apex predators of the marine
community? - ANS The apex predators are impacted by pollution in the environment
because they are the top of the marine food chain, where accumulation of pollution is quite
great.
A marine biologist explains that the salmon adapts to its environment through descent with
modification. What is "descent with modification"? - ANS A heritable trait can cause one
generation to be slightly different from another.
In the Galapagos islands, larger iguanas are more successful at reproducing and have more
offspring. How would the population change if larger body size also makes iguanas more
vulnerable to predatory birds? - ANS The population would be more balanced between
small, medium, and large body sizes because while larger iguanas reproduce more, smaller
iguanas avoid predators better.
What is overproduction? - ANS The species produces more young than can be supported by
the ecosystem.
What animals would you likely find in this habitat?
swamp with lots of trees - ANS Juvenile fish and shrimp
What prediction can be made about how the distribution of coral reef populations would be
affected if the oceans in which they live were to experience significantly more cloudiness of the
water? he coral population would decrease due to lack of sunlight. - ANS The coral
population would decrease due to lack of sunlight.
The average female Atlantic cod (Gadus morhua) produces two million eggs in a single
spawning. How does this relate to natural selection? - ANS More organisms are born than
can survive.
2
Page
@COPYRIGHT BRAINBARTER 2025/2026
