The human brain consumes up to 20% of the energy used the entire human body which is any other single organ. the brain represents inly 2%of the body wheight yet it recieves 15% of the cardiac output and 20% of the total body oxygen consumption.
Answer:
Nervous system: This systems helps the five sense organs (eyes, ears, nose, tongue, skin) which all contain nerves that send messages to the brain about what is happening. The brain produces a response which it sends via other nerves to the muscles.
Digestive system: This system helps to break down food into simpler substances so it can be used and absorbed into the body. It takes place in the alimentary canal (food tube), mainly in the stomach and small intestine. The digested food is absorbed into the blood.
Respiratory System: This system helps take in oxygen and removing waste carbon dioxide. Air enters the lungs by movement of the rib muscles and diaphragm. The oxygen is absorbed into the blood.
Reproductive system: This helps produce offspring. Eggs are produces by ovaries in a female and the sperm is produced in the testes of a male. They then try and fertilise the eggs.
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