the food eaten in one day is a diet and a balanced diet is a diet that contains all the required nutrients, in suitable proportions, and the right amount of energy.

The 6 types of nutrients are: Carbohydrates, Proteins, fats, vitamins, minerals, water.

Carbohydrates are needed for energy and they include starch and sugars. Staples food include potatoes, wheats, maize, also is sweet foods, which contain sugar.

They are needed for energy, and to make cell membranes. They act as an insulator, reducing heat loss from the body to the air. Also forms a layer around body organs such a skidneys, providing mechanical protections for them.

Are needed to build new cells for growth and are also used to make proteins including haemoglobin, insulin and anitbodies.

Organic substances which are only needed in tiny amounts. Vitamin C deficiency can cause scurvy(pains in the joints and bleeding gums.) and Vitamin D deficiency can cause ricket(softening of bones and they becoming deformed.).

Inorganic substances. Calium defiecieny causes brittle bones and teeth as well as poor blood clotting. Iron deficiency cause anaemia.

we get most of our water by drinking fluids, but some foods such as fruits also contain a lot of water.

helps in keeping the alimentary canal waorking properly. Peristalsis - rhythmical muscular contractions that move food through the alimentary canal. A source is the outer husk of cereal grains.

4 types of teeth, incisors, canines, pre-molars and molars.
Incisors are the front 8 teeth that are used to biting of pieces of food.
Canines are the pointed teeth at eith side used to tear food and for carnivores it is used to kill their prey.
Premolars are the teeth with broad, riged surfaces found between the canines and molars; they are used for grinding food to increase its surface area.
Molars are the teeth that are similar to premolars but are much broader and more ridged and also are used for grindign food to increase its surface area.

The structure of a tooth is that the tooth is embedded into the gum. the part of the tootth above the gum is covered in enamel(hardest substance, very difficult to break or chip.the comes the dentine( a living tissue beneath the enamel), then there is the pulp containing nerves and blood vessels. In the gum the tooth has cement, blood supply for the tooth.

By the time the food passes through the duodenum most of the large molecules have been fully digested to small ones. Carbohydrates have been broken down to glucose, proteins to amino acids, fats to fatty acids and glycerol. process is called absorption.

Very small finger-like projections that line the inner surface of the small intestine, greatly increasing its surface area. The length of it is about 1mm long.

microvilli are the tiny folds on the surfaces of the cells of the epithelium of the vilii in the small intestine..

The structure of a villi is that it has epithelium which one cell thick, then comes the blood capillaries that absorb amino acids, glucose, vitamins, mineral ions and water. then comes the lacteal that absorbs fatty acids and glycerol. Below the villi are the arteries that bring blood to the villi from the heart, and the hepatic portal vein takes the blood to the liver.