AP Biology Unit 8.1

What are organisms responding to?

Organisms respond to their environment and other organisms through behavioral or physiological mechanisms.

Why is response to the environment important?

It affects fitness and is subject to natural selection—organisms that respond well are more likely to survive and reproduce.

What is photoperiodism?

A physiological reaction of plants to the length of night or dark period.

What triggers flowering in long-day plants?

Short periods of darkness (e.g.

What triggers flowering in short-day plants?

Long periods of darkness (e.g.

What is phototropism?

Growth of a plant in response to light; auxin accumulates on the shaded side

What is auxin?

A plant hormone that regulates growth

What are diurnal animals?

Animals active during daylight.

What are nocturnal animals?

Animals active during the night.

What are crepuscular animals?

Animals active during twilight.

What is taxis?

Directed movement in response to a stimulus (positive or negative).

What is kinesis?

Undirected movement in response to a stimulus.

What is phototaxis?

Movement toward or away from light.

What is chemotaxis?

Movement in response to chemical signals.

What is geotaxis (gravitaxis)?

Movement in response to gravity.

What is the fight-or-flight response?

A rapid decision to flee or fight based on survival priority.

What is aposematism?

Warning coloration that signals predators to avoid attacking.

What is Batesian mimicry?

Harmless species mimic harmful ones to avoid predation.

What is Mullerian mimicry?

Two harmful species resemble each other to reinforce predator avoidance.

How do plants respond to herbivory?

They activate defense pathways and reallocate resources to reduce palatability.

What types of signals do organisms use to communicate?

Visual

What is an example of visual signaling?

Flower coloration attracts pollinators; dog snarls to threaten.

What is an example of audible signaling?

Vervet monkey alarm calls; cricket chirping to attract mates.

What is an example of tactile signaling?

Cat grooming kitten; bee waggle dance.

What is an example of electrical signaling?

Electric eels stun prey; sharks sense muscle-generated electric fields.

What is an example of chemical signaling?

Capsaicin deters mammals but not birds

What is territorial marking?

Animals use scent (pheromones) to mark and defend territory.

What are bird songs used for?

Attracting mates

What are pack behaviors?

Communication for territory defense

What are predator warnings?

Rattlesnake rattling

What are innate behaviors?

Instinctive

What are examples of innate behaviors?

Spider spinning a web

What are learned behaviors?

Behaviors acquired through experience; adaptive and flexible.

What are examples of learned behaviors?

Learning to hunt

What are cooperative behaviors?

Group behaviors that increase individual and population fitness.

What are examples of cooperative behaviors?

Pack hunting

What is kin selection?

Altruistic behavior that reduces individual fitness but increases relatives' reproductive success.

What are examples of kin selection?

Worker bees helping the queen; meerkats giving alarm calls.

What is the benefit of cooperative behaviors?

They increase the fitness of both the individual and the population.

Which example shows response to another organism?

Sharks sensing electric fields from fish.

Which example shows response to an abiotic factor?

A plant growing toward sunlight.

Which behavior is least likely to increase individual fitness?

Altruistic behaviors.

What is the difference between innate and learned behaviors?

Innate behaviors are fixed; learned behaviors change based on experience.

Which behavior shows communication to change another’s behavior?

A cheetah marking territory with scent.

What do poisonous animals use to prevent attacks?

Warning coloration.