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AP Biology Practice Quiz: Responses to the Environment

Written by AP Content Team, Verified for 2026 AP Exams, Last updated: May 2026

Test your understanding with short quizzes. This quiz has 15 questions to check your progress.

Question 1 of 15

A plant's leaves and stem grow towards a light source. This is an example of an organism's response to which of the following?

All Questions (15)

A plant's leaves and stem grow towards a light source. This is an example of an organism's response to which of the following?

A) An internal physiological cue

B) A change in its external environment

C) A cooperative behavior within a population

D) A learned behavior for reproductive success

Correct Answer: B

The light source is an external environmental factor. The plant's growth towards it is a physiological and behavioral response to this external change, as described in content points 1 and 3.

Many species of birds migrate to warmer climates during the winter months. How does this behavioral response most directly affect the overall fitness of these birds?

A) It decreases their fitness by exposing them to the dangers of a long journey.

B) It increases their fitness by allowing them to access more abundant food resources and suitable breeding grounds.

C) It has no effect on fitness, as it is an innate behavior that cannot be changed.

D) It alters their physiological responses to cold, making them more tolerant to future winters.

Correct Answer: B

According to content point 2, behavioral responses affect overall fitness. Migration is a behavior that increases the chances of survival and reproduction by moving to an environment with better conditions, thus increasing fitness.

A male peacock displays its large, colorful feathers to a female. This form of communication is an example of which type of signal?

A) Audible

B) Chemical

C) Tactile

D) Visual

Correct Answer: D

The peacock's feather display is a signal that is seen by the female. According to content point 5, this is a form of visual communication used to alter behavior, in this case, to attract a mate for reproduction.

Which of the following scenarios best illustrates how a response to an external cue can lead to differential reproductive success?

A) A squirrel buries nuts for the winter in response to decreasing day length.

B) A male firefly flashes a species-specific light pattern that attracts a female mate.

C) A bear enters a state of hibernation during the cold winter months.

D) A plant's roots grow downward in response to the force of gravity.

Correct Answer: B

Content point 5 states that communication can lead to differential reproductive success. The male firefly that produces the most effective visual signal is more likely to attract a mate and reproduce, passing on its genes. The other options are primarily related to survival.

Wolves hunt in packs to take down large prey that a single wolf could not. This behavior persists in wolf populations because it increases the likelihood of a successful hunt and feeding the pack. This is best described as an example of:

A) An individual physiological response to an internal cue.

B) A learned behavior that decreases the fitness of the individual for the good of the species.

C) A cooperative behavior that increases both individual and population fitness.

D) A response to an electrical signal that ensures differential reproductive success.

Correct Answer: C

Content point 6 explains that cooperative behaviors can increase individual and population fitness. By hunting together, each wolf has a better chance of eating and surviving, which in turn contributes to the success of the entire population.

A spider spinning a complex web without any prior observation or instruction is an example of an innate behavior. According to the principles of natural selection, why would such a behavior be favored?

A) Because the behavior is learned from other spiders in the population.

B) Because it is a random behavior with no impact on survival.

C) Because it increases the spider's chances of capturing food, thus increasing its survival and reproduction.

D) Because it is a physiological response to an internal cue like hunger.

Correct Answer: C

Content point 6 states that innate behaviors that increase survival and reproduction are favored by natural selection. A spider's web-spinning ability is crucial for obtaining food, which directly impacts its ability to survive and reproduce.

Organisms respond to changes in their environment through which two primary types of mechanisms?

A) Genetic and cellular

B) Reproductive and developmental

C) Behavioral and physiological

D) Innate and learned

Correct Answer: C

Content point 3 explicitly states, 'Organisms respond to environmental changes through behavioral and physiological mechanisms.' Innate and learned are types of behaviors, not the overarching categories of response mechanisms.

A female moth releases pheromones into the night air, which are detected by a male of the same species several kilometers away, causing him to fly towards her. This interaction demonstrates that:

A) Organisms can only respond to internal cues, which triggers a physiological change.

B) Learned behaviors are the primary driver of reproductive success in insects.

C) Organisms exchange information using chemical signals, which can alter behavior.

D) Tactile communication is vital for long-distance information exchange.

Correct Answer: C

This scenario is a classic example of chemical signaling. As stated in content points 4 and 5, organisms exchange information (the pheromone is the information) in response to a cue, and this chemical signal alters the male's behavior (flying towards the female).

A population of deer lives in a forest where the primary predator hunts by sound. A mutation arises that causes some deer to freeze in place for several minutes in response to a sudden noise, rather than running. Which statement best predicts the long-term consequence of this new behavioral response?

A) The freezing behavior will be selected against because it is not a physiological response.

B) The freezing behavior will be favored, and its frequency will likely increase in the population because it enhances survival and subsequent reproduction.

C) The behavior will have no effect on the population's success because it is a learned, not an innate, response.

D) The entire deer population will adopt the freezing behavior through cooperative learning, regardless of its effect on fitness.

Correct Answer: B

According to content point 6, responses to information are vital to natural selection, and behaviors that increase survival are favored. In an environment with a sound-based predator, freezing is a better survival strategy than running (which creates noise). This increased survival leads to increased reproduction for those with the trait, making it more common over time.

The feeling of thirst in a mammal is an internal cue that triggers the behavior of seeking and drinking water. This is an example of an organism responding to a change in its:

A) External social structure

B) Internal environment

C) Population density

D) External temperature

Correct Answer: B

Content point 1 explains that organisms have responses related to changes in their internal or external environment. Thirst is a physiological signal indicating dehydration, which is a change in the internal environment, leading to a behavioral response.

Which of the following provides the best explanation for how natural selection can shape the communication behaviors within a population?

A) All communication behaviors are innate and fixed, so they cannot be shaped by natural selection.

B) Natural selection only favors complex learned behaviors over simple innate behaviors.

C) Individuals whose communication signals most effectively lead to survival or mating are more likely to reproduce and pass on those signaling traits.

D) Communication behaviors are shaped by the environment but do not contribute to the overall fitness of a population.

Correct Answer: C

Content points 5 and 6 directly link communication, behavior, differential reproductive success, and natural selection. If a particular signal (visual, audible, etc.) makes an individual more successful at mating or surviving, that trait will be favored by natural selection and become more common in the population.

When a vervet monkey spots a predator, it gives a specific alarm call. Other monkeys in the group hear the call and respond appropriately, such as by climbing a tree for a leopard alarm or looking up for an eagle alarm. This complex interaction is vital for:

A) Establishing a reproductive hierarchy through tactile signals.

B) Exchanging information through audible signals to increase survival.

C) Responding to an internal physiological change in the environment.

D) Learning a new behavior that decreases individual fitness.

Correct Answer: B

This scenario shows organisms exchanging information (the specific type of predator) using audible signals (the alarm call), as described in content point 5. This alters the behavior of the group and, as stated in content point 6, is a behavior that increases survival and is favored by natural selection.

A dog learns to sit on command by being given a treat each time it performs the action correctly. This is a clear example of:

A) An innate behavior that is genetically determined.

B) A physiological response to an internal cue.

C) A learned behavior that alters the dog's response to an external cue.

D) A cooperative behavior that increases the fitness of the dog's population.

Correct Answer: C

The dog is not born knowing how to sit on command; it learns through experience and reward. This is a learned behavior. The command ('sit') is an external cue, and the dog alters its behavior in response to it. Content point 6 notes that both innate and learned behaviors can be favored.

The success of a population is most directly enhanced by behavioral responses that lead to which outcome?

A) Increased energy expenditure by individuals.

B) Decreased variation in communication signals.

C) Increased survival and reproductive rates.

D) Isolation of individuals from each other.

Correct Answer: C

Content point 2 states that behavioral responses affect overall fitness and contribute to the success of a population. Fitness is measured by survival and reproduction. Therefore, behaviors that increase these two factors will enhance the success of the population.

In a bee colony, worker bees, who are sterile, perform a 'waggle dance' to communicate the location of a food source to other workers. While the dancing bee gains no direct reproductive benefit, the behavior persists. Which concept best explains this phenomenon?

A) It is a simple physiological response to an external change in the environment.

B) It is a learned behavior that has no impact on the success of the population.

C) It is a cooperative behavior that increases the fitness of the population as a whole, ensuring the queen's reproductive success.

D) It is an example of a visual signal that leads to differential reproductive success for the individual worker bee.

Correct Answer: C

This is a classic example of a cooperative behavior that increases population fitness, as mentioned in content point 6. The individual worker does not reproduce, but its actions contribute to the survival and nourishment of the entire colony, including the reproductive queen. This ensures the propagation of the colony's genes, thus increasing the overall fitness of the population.