Chapter 4

Responses of Living Things

1. environment-Everything that surrounds a living thing

5. stimulus-anything that causes a living thing to react

2. external stimulus -Anything in an organism’s environment that causes it to react

4. response-a reaction to a stimulus

3. internal stimulus-anything within an organism that causes it to react

Notes1. Shivering and putting on a sweater are an example of

responses to cold. 2. A snake’s forked tongue helps it to smell. 3. Sea otters find food by being able to detect vibrations using

their whiskers. 4. An example of internal stimuli is hunger pains. 5. For a moth, the sound of a bat is an external stimulus. 6. All living things react to their surroundings. 7. Many animals have 5 senses. They are sight, hearing, touch,

taste, and smell. 8. Echolocation is a form of detection using sound waves. Bats

and dolphins use echolocation. 9. Plants and animals react to both external and internal stimuli. 10. Plants react to stimuli even though they do not have 5 senses.

Lesson 2: Inherited and Learned Behavior

Key Vocabulary

4. Learned behavior-A behavior that is taught of learned from experience

3. instinct-A complex pattern of behavior that organisms of the same type are born with

2. Inherited behavior-a behavior that an organism is born with and does not need to learn

1. behavior-The way that a living thing acts or responds to its environment

Notes1. Some animals hibernate, or go into a deep sleep, during the

winter months when food is scarce. 2. Birds, whales, fish, and insects migrate, or move to another

area, when it gets colder. 3. A reflex is a simple automatic inherited behavior. 4. As animals interact with their environment, they learn new

behaviors. 5. Examples of learned behaviors are riding a bike, grooming

each other, playing the piano, cooking, reading, speaking, and writing.

6. People and some animals can learn different behaviors. 7. Examples of an instinct are making a web, turtles moving

toward the ocean after birth, hibernating, migrating, and building a certain kind of nest.

8. Learning different behaviors can help an organism survive.