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Interaction is how living things connect with the world around them and with

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what's happening inside their bodies. It helps us stay safe, solve problems and

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keep healthy. We get signals called stimuli from things around or inside us

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and our bodies create responses to react to those signals. This is how we adjust

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to changes and stay balanced in our environment. Stimuli and responses are

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important ways that our bodies react to changes. A stimulus is something that

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happens around us or inside us. There are two kinds of stimuli. External stimuli.

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These come from outside your body. They are things like sounds, sights or touches

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that happen around you. For example, if you hear a loud noise you might cover

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your ears. The noise is the external stimulus and covering your ears is the

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response. Another example is when you see a ball and you catch it. The ball is the

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stimulus and catching it is your response. Internal stimuli. These come

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from inside your body. Your body sends signals to let you know something is

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happening. For example, when you're hungry your stomach might growl or you feel

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like you need to eat. That feeling of hunger is the internal stimulus, and eating food would be

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your body's response. Another example is when you feel thirsty, which is your body telling you to

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drink water. A response is what we do because of that stimulus. There are two types. Motor responses.

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This involves moving our muscles to do something. There are two types of motor responses.

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Voluntary responses. These are movements you decide to do with your brain. For example,

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if you see a ball and you decide to kick it, that is a voluntary response. You think about

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what you want to do and then make it happen. Involuntary responses. These are movements

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that happen without you thinking about them. Your body reacts automatically and these are

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usually controlled by your spinal cord. A good example is when you accidentally

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touch something hot and your hand pulls away before you even realize it. This is

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called a reflex and your body does it to protect you. Another good example is when

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someone pops a balloon near you. You are likely to scream, close your eyes and

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move your hands. Glandular responses. This involves your glands releasing something.

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Glands are little organs inside your body that make things like sweat saliva

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or hormones. For example when you see or smell delicious food your mouth starts

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to water because your salivary glands make saliva. This is your body's response

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to getting ready to eat. Another example is when you feel hot and your body

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releases sweat. To sum up stimuli are like signals that tell your bodies

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what's going on and responses are how your body reacts. Whether it's moving your muscles or

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getting your glands to work, your body always has a way to respond to keep you safe and healthy.