Biology Final Exam Review 2

1. Why do all mammals have hair on their bodies?

They need hair in order to be called mammals.

Each species decided to grow hair.

As a group, all mammals decided to grow hair.

They had a common ancestor.

Organisms don't decide which traits they want to have. However, when two different species have similar traits this is an indication that they probably descended from the same common ancestor.

Explanation

Organisms don't decide which traits they want to have. However, when two different species have similar traits this is an indication that they probably descended from the same common ancestor.

2. An area where a population of wolves lives is getting colder. Even though the wolves do not have predators, they often die as a result of the cold temperatures. In this climate, natural selection should favor individuals that possess which of the following?

White fur

Thicker fur

Sharp claws

Blue eyes

Having thick fur would help protect the wolves from the very cold weather.

Explanation

Having thick fur would help protect the wolves from the very cold weather.

3. Scientists can compare DNA sequences of different species of animals. The species that are most closely related will

Have the greatest number of common DNA sequences

Have the fewest number of common DNA sequences

Start to mutate

Have more sex-linked traits

If you get a table of DNA sequences, compare and count the number of similar sequences. Those with the greatest number of similar sequences are most closely related.

Explanation

If you get a table of DNA sequences, compare and count the number of similar sequences. Those with the greatest number of similar sequences are most closely related.

4. The mole rat is an animal that avoids predators by living underground. Its long claws and teeth allow it to dig deep holes. Scientists believe the ancestors of the mole rat lived above ground and had shorter claws and teeth. Which of these processes resulted in the long claws and teeth found in the modern mole rat?

Natural selection

Selective breeding

Genetic engineering

Asexual reproduction

The environment "prefers" these traits of long claws and teeth because they help the organism to survive.

Explanation

The environment "prefers" these traits of long claws and teeth because they help the organism to survive.

5. A population of land snails colonized a field of light-colored grasses. At first, the population contained two types of snails, one with dark shells and another with light shells. After ten years, most of the snails had light-colored shells. What process led to the increase in the number of snails with light-colored shells?

Mutation

Succession

Natural selection

Genetic engineering

The increase in the number of snails with light-colored shells is due to natural selection. Natural selection is the process in which individuals with traits that are better suited to their environment have a higher chance of surviving and reproducing. In this case, the light-colored shells provided a better camouflage against the light-colored grasses, allowing those snails to avoid predators and survive. Over time, the population became dominated by snails with light-colored shells as they had a higher reproductive success. This is a classic example of natural selection driving evolutionary change.

Explanation

The increase in the number of snails with light-colored shells is due to natural selection. Natural selection is the process in which individuals with traits that are better suited to their environment have a higher chance of surviving and reproducing. In this case, the light-colored shells provided a better camouflage against the light-colored grasses, allowing those snails to avoid predators and survive. Over time, the population became dominated by snails with light-colored shells as they had a higher reproductive success. This is a classic example of natural selection driving evolutionary change.

6. Cleaner fish feed off of the algae, fungi, and other microorganisms that are found on the teeth of larger fish. Another species of fish, called mimics, look like cleaner fish. They are able to approach the larger fish and remove food from the teeth as well. If the mimic fish populations grow to outnumber the cleaner fish, the ________.

Eating patterns of the larger fish would change or it would die.

Eating patterns of the cleaner fish would change or it would die.

Cleaner fish and mimic fish would interbreed and become one species.

Food found on the larger fish would increase.

Since mimic fish are able to approach the larger fish and get food from their teeth, the food source for the cleaner fish would decrease. Therefore, the cleaner fish would have to bealbe to find other sources of food or their numbers would decrease.

Explanation

Since mimic fish are able to approach the larger fish and get food from their teeth, the food source for the cleaner fish would decrease. Therefore, the cleaner fish would have to bealbe to find other sources of food or their numbers would decrease.

7. A store owner uses an insecticide to eliminate cockroaches in his kitchen. Although the insecticide killed most of the cockroaches when it was first used, after several months, it no longer kills them.
What process occurs that causes the insecticide to be ineffective against the cockroaches?

Cloning

Natural selection

Speciation

Succession

Natural selection is the process by which the environment "chooses" organisms with traits that help survival. In this case, it would be the cockroaches ability to withstand the insecticide. In time, there would be more and more of these individuals, because those with the trait would survive and be able to have babies who also tend to possess the trait.

Explanation

Natural selection is the process by which the environment "chooses" organisms with traits that help survival. In this case, it would be the cockroaches ability to withstand the insecticide. In time, there would be more and more of these individuals, because those with the trait would survive and be able to have babies who also tend to possess the trait.

8. Which of the following does NOT lead to genetic recombination?

Meiosis

Asexual reproduction

Crossing over

Independent assortment of homologous chromosomes

Asexual reproduction does not lead to genetic recombination because it involves the production of offspring that are genetically identical to the parent. In asexual reproduction, there is no exchange or mixing of genetic material between different individuals, so there is no recombination of genes. Instead, offspring are produced through processes such as binary fission or budding, where the genetic material is simply copied and passed on without any variation or rearrangement. Therefore, asexual reproduction is not a mechanism for introducing genetic diversity or recombination into a population.

Explanation

Asexual reproduction does not lead to genetic recombination because it involves the production of offspring that are genetically identical to the parent. In asexual reproduction, there is no exchange or mixing of genetic material between different individuals, so there is no recombination of genes. Instead, offspring are produced through processes such as binary fission or budding, where the genetic material is simply copied and passed on without any variation or rearrangement. Therefore, asexual reproduction is not a mechanism for introducing genetic diversity or recombination into a population.

9. Which of the following primarily uses asexual reproduction?

Animals only

Bacteria only

Plants only

Bacteria and plants only

Bacteria primarily uses asexual reproduction. Bacteria reproduce by a process called binary fission, where the cell divides into two identical daughter cells. This process allows bacteria to rapidly multiply and colonize new environments. In contrast, animals primarily reproduce sexually, involving the fusion of gametes from two parents. Plants, on the other hand, can reproduce both sexually and asexually, with asexual reproduction methods such as vegetative propagation or budding. Therefore, the correct answer is bacteria only.

Explanation

Bacteria primarily uses asexual reproduction. Bacteria reproduce by a process called binary fission, where the cell divides into two identical daughter cells. This process allows bacteria to rapidly multiply and colonize new environments. In contrast, animals primarily reproduce sexually, involving the fusion of gametes from two parents. Plants, on the other hand, can reproduce both sexually and asexually, with asexual reproduction methods such as vegetative propagation or budding. Therefore, the correct answer is bacteria only.

10. Eukaryotic organisms such as plants, animals, and fungi all share a unicellular prokaryotic ancestor. Which of the following structures played an important role in the development of eukaryotic organisms from prokaryotic organisms?

Nucleus

DNA

Ribosome

Cell membrane

This is really asking what makes the eukaryotic cell different form the prokaryotic cell and we all remember that eukaryotes have a nucleus and other complicated organelles, where prokaryotes don't.

Explanation

This is really asking what makes the eukaryotic cell different form the prokaryotic cell and we all remember that eukaryotes have a nucleus and other complicated organelles, where prokaryotes don't.