Question 1

The idea that evolution proceeds with long periods of stasis with relatively brief bursts of fast evolutionary change is

Accepted Answer

The idea that evolution proceeds with long periods of stasis with relatively brief bursts of fast evolutionary change is known as punctuated equilibrium.

Question 2

The process by which new species originate

Accepted Answer

The process by which new species originate is called speciation. It involves the evolution of differences between populations that eventually lead to the development of new species. It is an ongoing process that has occurred throughout the history of life on Earth.

Question 3

The idea that evolution proceeds in small,incremental changes over many generations is

Accepted Answer

Gradualism refers to the concept that evolution occurs through small, incremental changes over long periods of time. This is contrasted with punctuated equilibrium, which proposes that evolutionary change occurs in short bursts of rapid change followed by periods of stability. The other answer choices represent different mechanisms of reproductive isolation.

Question 4

The type of reproductive isolation in which two populations live in the same habitat but remain isolated from one another due to one being active during the daytime only and the other being active only during the night is

Accepted Answer

This is an example of temporal isolation, where the populations are isolated due to differences in the timing of their activities (daytime vs night-time). Behavioral isolation refers to differences in behavior that prevent mating, gametic isolation refers to differences in gametes that prevent fertilization, mechanical isolation refers to physical differences that prevent mating, and sexual selection refers to mate choice based on particular traits.

Question 5

The type of reproductive isolation in which offspring are infertile because their chromosomes cannot align correctly during meiosis because of a different number of chromosomes being inherited from the two parents is

Accepted Answer

This type of reproductive isolation is called hybrid infertility or hybrid sterility. It occurs when two different species mate and produce offspring, but the offspring are infertile because they have an odd number of chromosomes or cannot properly pair their chromosomes during meiosis. This is common in hybrid animals such as mules (the offspring of a horse and a donkey) which are typically sterile.

Question 6

It is believed that the two main reasons for mass extinctions in Earth's history have been

Accepted Answer

The two main reasons for mass extinctions in Earth's history have been the collision between Earth and a large celestial body (such as the asteroid that caused the extinction of the dinosaurs) and the shifting of Earth's continents (known as plate tectonics, which can cause large-scale changes in climate and habitats). There is some evidence that human intervention has also played a role in more recent extinctions, but this is not considered to be one of the two main reasons for mass extinctions throughout Earth's history. Similarly, while global warming may contribute to extinctions, it is not considered to be one of the two main historical causes.

Question 7

The type of reproductive isolation in which two populations are separated due to the sperm cells of one not being able to recognize the egg cells of the other is

Accepted Answer

Gametic isolation occurs when the sperm cells cannot recognize and fertilize the egg cells of another population, thereby preventing gene flow between them. This can occur due to differences in the molecular structures of the gametes or changes in the environment surrounding the gametes. Hybrid inviability refers to offspring that do not develop properly and die before reaching reproductive age, while hybrid infertility refers to offspring that are sterile or have reduced fertility. Temporal isolation refers to populations that reproduce at different times and ecological isolation refers to populations with different habitat preferences.

Question 8

The impact of a large meteorite with Earth would have most likely caused mass extinctions by

Accepted Answer

A collision with a large meteorite would create a large impact crater and can cause fires, earthquakes, and tsunamis. The dust thrown up into the atmosphere would prevent sunlight from reaching the Earth's surface, causing a reduction in photosynthesis and plant life as well as a prolonged drop in surface temperatures. This would lead to the extinction of various species across the food chain, including primary producers, herbivores, and carnivores. Therefore, the best option is D, creating large clouds of dust that blocked out sunlight and destroying plant life.

Question 9

The types of living organisms on Earth have changed over time - new species have originated and existing species have disappeared.This is an example of

Accepted Answer

The fact that the types of living organisms on Earth have changed over time and that new species have originated and existing species have disappeared is an example of macroevolution, which refers to large-scale evolutionary changes that occur over long periods of time. The other options, such as speciation, extinction, alternation of generations, and hybridization, are more specific processes or phenomena that contribute to macroevolution.

Question 10

An example of polyploidy is found in a plant

Accepted Answer

Polyploidy refers to the condition in which an organism has more than two sets of chromosomes. In plants, polyploidy can result from the fusion of two or more diploid cells, or from the failure of cell division after chromosome replication. Examples of polyploid plants include wheat, cotton, and strawberries. Polyploidy can result in larger and more vigorous plants, as well as increased genetic diversity.

Question 11

The rate of background extinctions is

Accepted Answer

The rate of background extinctions is typically estimated to be between 0.1 to 1.0 species per year per million species, which aligns with choice A.

Question 12

The scientist given credit for devising the two-word naming system of all living organisms is

Accepted Answer

The scientist given credit for devising the two-word naming system of all living organisms is Carolus Linnaeus.

Question 13

The process by which species cease to exist

Accepted Answer

Extinction is the process by which species cease to exist.

Question 14

The type of reproductive isolation in which the two populations are separated by the habitat each utilizes is

Accepted Answer

Habitat isolation is the type of reproductive isolation that occurs when two populations are separated because they inhabit different habitats or ecological niches. This can prevent interbreeding between the two populations even if they come into contact with each other. Mechanical isolation occurs when the sexual organs of two species are incompatible, hybrid inviability occurs when the offspring of two species are not viable, behavioral isolation occurs when species have different courtship or mating behaviors, and temporal isolation occurs when species reproduce at different times.

Question 15

Which of the following is not a type of prezygotic reproductive isolation?

Accepted Answer

Hybrid infertility is a postzygotic reproductive isolation mechanism, as it occurs after the formation of a hybrid zygote. The other options (A, B, D, and E) are all examples of prezygotic reproductive isolation mechanisms.

Question 16

Postzygotic isolation barriers prevent

Accepted Answer

Postzygotic isolation barriers occur after fertilization has taken place. Choice A is the correct answer as it specifically relates to the inability of a hybrid embryo to develop into a fertile adult. Choice B is incorrect because fertilization has already occurred. Choice C is incorrect as it relates to prezygotic isolation barriers. Choice D is incorrect as not all answers can be correct. Choice E is also incorrect as it relates to prezygotic isolation barriers.

Question 17

Species such as mice have a better chance of surviving sudden environmental change than elephants because

Accepted Answer

Mice reproduce quickly and have shorter generation times, which means they can adapt and evolve faster to sudden environmental changes, compared to elephants that have longer generation times and reproduce slowly. Therefore, mice have a better chance of survival in such situations.

Question 18

Centimeter-thin layers of earth that are rich in iridium give evidence to support the

Accepted Answer

Centimeter-thin layers of earth that are rich in iridium are evidence to support the impact theory, which proposes that the extinction of the dinosaurs was caused by a large asteroid impact on Earth that led to catastrophic environmental changes. Iridium is rare on Earth's surface but common in asteroids and comets, providing evidence for the impact theory.

Question 19

Biologists divide mechanisms of reproductive isolation into

Accepted Answer

Biologists divide mechanisms of reproductive isolation into prezygotic (before fertilization) and postzygotic (after fertilization) mechanisms. Prezygotic mechanisms include behavioral, temporal, mechanical or gametic isolation while postzygotic mechanisms include hybrid inviability or infertility. Geographical isolation is a type of prezygotic mechanism, while asexual and sexual reproduction are not considered mechanisms of reproductive isolation.

Question 20

Polyploidy is

Accepted Answer

Polyploidy, or having multiple sets of chromosomes, is common in plant species. It is much less common in fungal, animal, and bacterial species.

Quiz 14: Speciation and Extinction