The body's control network

The idea

Nervous tissue forms the body's control and coordination network, with the brain as the control centre; voluntary and involuntary muscles cannot function independently and act on instructions from nervous tissue.

Hot and fast

You touch a hot pan and your hand jerks away. During a race, your heart beats faster. You did not plan either.

What passes instructions to the muscles in both cases?

• Nervous tissue
• Bone
• Cartilage

Follow the instructions

Choose each situation and watch which muscle gets instructions.

Muscles take instructions

Both muscles in the picture, the voluntary arm muscle and the involuntary heart muscle, did their work on instructions from nervous tissue. Neither works on its own. The brain is the control centre.

Nervous tissue forms the body's control and coordination network, with the brain as the control centre. Voluntary and involuntary muscles cannot function independently: they act on instructions from nervous tissue.

Notes

Nervous tissue is the body's control network, and the brain is the control centre. Muscles act on its instructions.

Check yourself

Which tissue forms the body's control and coordination network?

Which part acts as the control centre of the body?

Can voluntary and involuntary muscles function independently?

During exercise the body needs more oxygen. What does the brain do?

• Connective tissue. Connective tissue connects and supports other tissues, such as blood and bone.
• Epithelial tissue. Epithelial tissue forms the outer covering of the body and lines internal organs.
• Nervous tissue — correct. Yes!
• The brain — correct. Yes!
• The heart. The heart beats on signals from the brain, for example faster during exercise.
• A skeletal muscle. Muscles receive instructions from the nervous tissue. They are not the control centre.
• Yes, voluntary muscles work without any instructions. Both voluntary and involuntary muscles receive instructions from nervous tissue.
• No, they receive instructions from nervous tissue — correct. Yes!
• Yes, the heart muscle works without any instructions. The heart muscle is involuntary, and it too acts on instructions. During exercise the brain signals it to beat faster.
• It signals the heart to stop beating. A heart that stops cannot meet the body's increased oxygen demand. The brain signals it to beat faster.
• It sends no signals to the muscles. Muscles act on instructions from nervous tissue, so the brain does send signals.
• It signals the heart to beat faster — correct. Yes!