Human nutrition

Diet containing the correct quantities of nutrients required to maintain a healthy body.

Protein, carbohydrates, fats and oils, vitamins and mineral ions, fibre and water

Broken down to make amino acids, used to create other proteins for cells eg, enzymes. Protein comes from egg, dairy, meat, fish, legumes, nuts and seeds.

Broken down to simple sugars used for respiration (To create energy for cells). Carbs come from, rice, bread, potatoes, pasta and yams.

Distriputed around the body. Helps maintain body temperature aswell as being a store for energy, supplying molecules for respiration if diet is lacking. Sources of fats and oils include: dairy, nuts, avocados, and oily fish.

Required in small amounts for bodily function. Cannot be produced by the body. Cooking foods destroys some vitamins. Lack of vitamins causes deficiency diseases.

Vitamin C - Healthy skin, teeth and gums + keeps blood vessel lining healthy. Sources: Raw citrus fruits, green vegetables, potatoes Vitamin D - Strong bones and teeth. Sources: Fish, eggs, liver, cheese and milk. Calcium - Strong teeth, bones and helps blood flow. Sources: Milk and eggs Iron - Used to create haemoglobin in red blood cells. Sources: Red meats, liver and kidneys, leafy green vegetables ( spinach).

Made from plants cell wall. Adds bulk to food so it can easily pass through the digestive system by peristalsis. Prevents constipation. Sources: Cabbage, brown rice and wholegrain wheat.

Necessary for all life processes. Lost through sweat and excretion and must be replaced reguraly to maintain health.

Ingestion - taking substances into the body digestion - breakdown of food absorption - movement of nutrients from intestines to blood assimilation - use of nutrients by cells egestion - undigested food removed as faeces

Continuous tube through the body from mouth to oesophagus, stomach, small intestine, large intestine and anus. Considered to be outside the body

Liver, pancreas, salivary glands and gall bladder

Teeth and tongue break food into smaller pieces

Moves food from mouth to stomach by waves of muscle contractions (peristalsis)

Enzymes secreted to start protein digestion + movement of muscular walls churn food into a liquid.

Duodenum - Secretions from gall bladder and pancreas enter to complete digegstion. Ileum - Digested food molecules and water absorbed

Colon - Water absorbed from remaining material rectum - faeces + dead cells from lining of the alimentary canal + Bacteria are compacted and stored anus - Faeces egested through a sphincter

Produce liquid saliva, moistens food to be swallowed and contains enzymes which break down starch.

Secretes digegstive enzymes in an alkaline fluid into the duodenum

Contractions of muscles in the walls of the alimentary canal to move food.

Stores bile to be released in the small intestine.

Mouth - Food is broken down into smaller pieces by chewing of teeth. Stomach - Movements of muscular wall churn food into a liquid called chyme. Small intestine - Bile breaks down fats and oils into small droplets. Physical digestion does not have any chemical change to the food molecules.

Breaking food into smaller pieces increases the surface area for enzymes in chemical digestion.

Enzymes breakdown large insoluble food molecules into smaller soluble molecules which can be absorbed by the blood. Glucose, vitamins, minerals and water are already small enough to pass through alimentary canal walls.