Digestion and nutrition

Balanced diet

The correct proportions of the 7 nutrient groups to maintain a healthy body

Vitamins

Nutrients needed in small amounts for a healthy body

Minerals

Needed for ley chemicals in the body

Carbohydrates

An energy source e.g bread

Lipids

An energy source e.g butter

Protein

Grows and repairs tissues

Fibre

an indigestible food that maintains a healthy gut

Ingestion

Food is taken into the body

Scurvy

Vitamin C deficiency

Rickets

Calcium deficiency

Blindness

Vitamin A deficiency

Digestion

Large insoluble molecules are broken into small soluble molecules

Absorption

When small soluble molecules pass through the walls of the digestive system into the bloodstream

Assimilation

Small molecules join together to form new tissues in the body

Egestion

Undigested food is taken out the body

Enzymes

Biological catalysts that speed up chemical reactions

Amylase

A digestive enzyme that breaks starch into glucose

Protease

A digestive enzyme that breaks proteins into amino acids

Lipase

A digestive enzyme that breaks down lipids into fatty acids and glycerol.

Muscular tissue

Moves food along the digestive system and keeps it well mixed

Glandular tissue

Produces enzymes

Hydrochloric acid

Provides the correct pH for protease to work

Mouth

Area where digestion begins

Oesophagus

Tube transporting food from the mouth to the stomach

Stomach

The muscular sac where the digestion of proteins take place

Small intestine

Long tube where small soluble molecules are absorbed into the bloodstream

Colon

Where water is absorbed into the bloodstream

Dependent variable

The variable that you measure

Control variable

The variable that is kept the same because changing it would change the dependent variable

Independent variable

The variable you change

Control experiment

A comparison experiment showing that the results obtained are due to the presence of the independent variable