Please please help me out!
1. How does the nervous system kick-start the process of digestion?
2. What is the function of the excretory system?
3. How are the nutrients extracted by the digestive system used in the body?
4. What is the function of the respiratory system?
5. How are the circulatory and respiratory systems linked?
6. What is the purpose of the skeletal system?
7. What does the muscular system do?
8. What is the function of the nervous system?

Look below for answers.

Explanation:

It's been a while since I've done biology, but here are my answers based on my past knowledge and a little research:

1. Chewing your food helps jump-start the digestive process because you are physically breaking down your food while also stimulating your mouth to create saliva which will begin to chemically break down food.

2. The excretory system's primary function is to excrete waste (urea, uric acid, carbon dioxide) from the body.

3. Nutrients extracted by the digestive system are distributed through out the body for a multitude of functions. Some provide growth energy for muscles or other structures, while others, like ions, provide more specific functions like signal transmition.

4. The resperatory system's primary function is to help provide an exchange of gases that are essential to cell respiration and other bodily functions.

5. They are linked through a couple of different features; both work together to provide oxygen and nutrients to cells, and both work together to create homeostasis.

6. The purpose of the Skeletal system is to provides structure for our body, assists with movement, provides protection for our important organs, makes blood cells, and also stores and releases mierals and fat.

7. The muscular system purpose is to provide movement, but it also  provides stability for our joints, maintains posture, and gives us heat.

8. The function of the nervous system is to be the body's control and center for communication between the bodies limbs and functions.

Hope this helps!

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