Stomach - Food is mixed with enzymes or special digestive substances in the stomach juices. These break down the food into a soup like mixture and help the body to absorb the nutrients that it needs.

The 'soup-like' mixture from the stomach is passed along the small intestine by waves of muscle contractions. It is here that a lot of the nutrients from food are absorbed into the bloodstream.

The large intestine contains over 400 different species of bacteria that break down and utilise the undigested residues of our food, mostly dietary fibres. As the watery contents move along the large intestine, water is absorbed and the final product - poo - is formed, which is stored in the rectum before excretion from the body.

When poo reaches the rectum a message is sent to the brain that poo is ready to leave the body. If poo doesn't leave the rectum regularly it will build up, dry out and harden and this is when constipation may occur and poo might start to back up in the large intestine because the rectum is full.

Produces bile, which helps carry away waste and break down fats in the small intestine during digestion .

The kidneys act as filters and produce wee as a waste product of the body.

These are the tubes that carry the wee from the kidneys to the bladder. These break down the food and help the body to absorb the nutrients that it needs.

This is where wee is collected before it leaves the body. It is like a balloon and will expand to hold wee until it is full. It then sends a message to the brain that it needs to empty. Sometimes, this message doesn't wake you up so the bladder empties whilst you are asleep. And in the day, the message can be too urgent so doesn't give you enough time to get to the toilet so you might have wetting accidents in the day too.

This is a narrow tube which carries wee from the bladder to leave the body