Biology Unit 3 Continued

HideShow resource information

How the small intestine is adapted for the absobtion of food

Very long (plenty time for absorption)

Many Villi (large surface area)

villi, no blood capillaries (food to pass into)

Villi have lacteals (fat absorption)

Villi Walls, one cell think (easy absorption of food molecules)

Exchance surfaces in animals

alveoli, small 'sacs', end of bronchioles, gas exchange takes place, maximise diffusion of oxygen + carbon dioxide

gas/solute exchange, depends on large surface area, moist surfaces, short diffusion distances, large concentration gradient

The Circulatory System

transport substances e.g. oxygen & glucose, to cells where used, removes waste, e.g. carbon dioxide, urea

made up of 3 parts:

- the heart

- the blood vessels

- the blood

The Heart

 cardian muscle, two pumps, right side pumps blood to lungs, left side pumps blood round the body, top chambers = atria, lower chambers…


No comments have yet been made

Similar Biology resources:

See all Biology resources »