Unit Test — Unit test Answers

Which best describes biogeographic isolation?

Horses and zebras can be bred to produce a zorse, which is infertile. Which is most likely the reason zebras and horses are considered separate species?

Which best illustrates a result of natural selection?

Consider the generalized cladogram of fish.A fossilized fish is found that has jaws but no true bones. Where does this fossil belong on the cladogram?

Why are the Miller-Urey experiments essential to the theory of evolution?

Henry was studying two populations of the same species of lizards. One population lived on an island and the other lived on the mainland. Both populations were affected by a hurricane that hit the island and the mainland with equal force. A year later, Henry was testing the gene frequency and saw a decrease in genetic variation in the island species, but not in the mainland species. Which best describes a conclusion he might have reached?

Consider the two male oryx that are shown below.Which of Charles Darwin’s main points is depicted in the image?

A scientist is trying to determine the relationship between clams, snails, and squid. When she generates a molecular clock, she is surprised to see that clams and squid are more closely related than clams and snails. Which did the molecular clock data show?

Which best describes the fossil record?

Jezelyn needs to create a project that shows geographic isolation in action and decides to make a video. Which of the following would make the best project?

A student has written a paper about a deer population that was separated when a canyon developed between members of the group. In her paper, she showed that the two groups adapted differently and can no longer interbreed. What would be the best title for her paper?

A biology teacher asks students to give examples of genetic variations that support the idea that changes in a population’s environment affect genetic variation. Which is the least supportive example?

Which of the following best defines a gene pool?

A bird that preys on moths is introduced to the habitat with moths and trees like the ones shown below. What will most likely happen to the population of moths in this habitat?

In a cladogram, when does a group of organisms branch off?

Mr. Morales is teaching a lesson on classification. He says that spiders are classified as a different group than insects because they have eight legs instead of six legs. He explains that spiders evolved first. Mr. Morales also says that having eight legs is the derived trait that separates the two groups. Antonio thinks Mr. Morales is wrong. Which piece of information is Antonio considering?

Babies with very low or very high birth weight are less likely to survive. The graph shows the percentage of babies born at different weights.Which statement is a valid claim that could be made using the data in the graph?

Thylacosmilus is a marsupial, and Smilodon is a mammal. Thylacosmilus and Smilodon both have saber teeth, but they do not share an ancestor that had saber teeth. What are saber teeth for these organisms?

Scientists notice structural similarities between fossils of a land animal and an aquatic organism. They know the similarities are not a result of the two organisms having to adapt to similar environments. What can they attribute the structural similarities to?

Which type of selection leads to increased phenotypic and genetic variation?