NUTRITION

NUTRITION is the function that allows the cells of living things to have the energy and tissues they need to perfurm their functions. Four systems take part un nutrition: the digestive system, the respiratory system, the circulatory system and the excretory system.

DIGESTIVE SYSTEM

It is charge of digestion: it changes food into the nutrients cells need.

RESPIRATORY SYSTEM

• It is in charge of breathing: it takes oxygen from the air that cells need and expels carbon dioxide.
• Breathing has two processes: lung ventilation and gas exchange.



EXCRETORY SYSTEM

• It is in charge of excretion: it eliminates waste substances carried by blood.
• it is made up of the sweat grands of the skin and the urinary tract

"Once upon a time.....the life" THE SKIN

CIRCULATORY SYSTEM

• It is in charge of circulation: it transports nutrients and oxygen to the body's cells.
• It is made up of the heart, blood and blood vessels.
• Human circulation is closed and double.