Mouth:

• take in food

• crush food with the teeth

• amylase is added to the food

Oesophagus:

• Carry down food to the stomach

Stomach:

• churn the food

• add acid to the food

Small intestine:

• further digestion by enzymes

• absorption of digested food into the blood.

Large intestine:

• water is absorbed into the blood

• the waste left is prepared for egestion

Salivary glands:

• make saliva, which contains an enzyme, amylase, to break starch down to small sugars

Liver:

• produces liquid bile, which helps digest fat

• regulates the amount of... (More)

BIODIVERSITY

Biodiversity - is the variety of living species on earth.

• Natural ecosystems can have a large number of species, when humans interfere with one species in the natural ecosystem they can accidentally affect other species or even the entire ecosystem.
• It is important to make sure that in the future we will have water, materials, and resources to protect human health and our environment which means we have to use our resources wisely and with sustainability.

Sustainability - means maintaining the world we live in for future generations of people and species.

Human activities can threaten biodiversity by:

• deforesting... (More)