Respiration and Circulation
All Living cells need to respire to release energy.
Energy is needed for organisms to stay alive- to make new substancer and to help them move.
Respiratrion requires oxygen so its called aerobic ( with air) respiration. Its chemical reaction is..
Glucose + oxygen -------- carbon dixodie + water
Glucose comes from a digestion of carbohydrates. Absorbed into the blood by the small intestine, then carried around the body dissolved in the plasma of the blood. Travels through the blood vessels and is pumped by the heart. THE HEART AND THE BLOOD VESSELS FORM THE CIRCULATORY SYSTEM.
Oxygen is absorbed from the air by the lungs. THE LUNGS ARE PART OF THE BREATHING SYSTEM ( RESPIRATORY SYSTEM)
The ALVEOLI ( air sacs) give the lungs a large surface area so that oxygen can quikly diffuse from the air inside the lungs into the blood…