Food and Nutrition

what is a diet?

the food you eat to maintain a healthy body

what foods do you need for a balanced diet?

• carbs

• proteins

• fats

• fibre

• vitamins

• water

lack of vitamin C

scurvy - joint pain, tiredness, weakness

lack of calcium

rickets - soft bones, poor growth

lack of iron

anemia - diziness, lightheadedness, weakness, pale skin

obesity

more calories consumed than burned, increased risk of diabetes and heart disease

heart disease

to much fat in the diet - chest pain, heart attack

bacteria

gut bacteria helps to digest food and prevents diseases such as diabetes

how are substances absorbed in the digestive system?

nutrients are absorbed in the small intestine and stomach, and water is absorbed in the large intestine. most substances are absorbed into the bloodstream

small intestine adaptions?

• covered in villi, which increase surface area to help absorbtion

• the walls of the small intestine are one-cell thick, allowing soluble molecules to diffuse into the bloodstream

function of the mouth

ingestion, chewing food to break it down

function of salivary glands

produces saliva, which has enzymes to break it down

function of oesophagus

food is pushed down it to the stomach using peristalsis

function of stomach

food is broken down by enzymes and hydrochloric acid

function of small intestine

more enzymes are used to break down food. carbs, proteins and fats are broken down, and soluble molecules are absorbed into the bloodstream

function of large intestine

absorbs excess water

function of rectum

food that can’t be digested is stored as faeces

function of anus

food is egested