UNIT 5: FOOD AND NUTRITIONANAYA Basic Competences (pages 6-7; 8-9)Food and nutrientsWe eat food every day. Our bodies change food into small substances called nutrients that give us energy and help us to grow.

We also need oxygen to have energy.

Our bodies make waste substances that we eliminate. All these processes together are called nutrition.

Systems that take part in nutrition

• The digestive system changes food into nutrients that go into the blood.

• The circulatory system takes nuttier and oxygen around the body.

It separates waste substances.

• The respiratory system takes oxygen from the air and releases other gases

• The excretory system eliminates waste substances.

Activity: Match the columns, write the complete sentences in your notebook.

The circulatory system * * takes oxygen from the air.

The excretory system * * changes food into nutrients.

The digestive system * * takes nutrients around the body.

The respiratory system * * eliminates waste substances.

Where does food come from?

•Meat, fish, eggs and milk come from animals. They are rich in proteins and fat.

•Oil, fruit, vegetables and cereals come from plants. They are rich in carbohydrates and vitamins.

•Other food, such as salt, comes from minerals.

Nutrients

Our bodies need a variety of healthy foods. Each food gives us different types of nutrients.

• Proteins make the muscles strong, move substances through the blood and make the body’s defences strong. We find proteins in meat, fish, eggs and milk.

• Fats give us energy and protect us against the cold. We find fats in oil and butter.

• Carbohydrates give us energy. We find them in bread, cereals, rice, pasta and vegetables.

• Vitamins and minerals are important for the nervous system and make our muscles work well. We find them in fruit and vegetables.

Why is it important to brush our teeth after every meal?

What is digestion?

Our bodies change food into nutrients in the digestive system. This process is called digestion.

The digestive system

The digestive system is a long tube that has different parts.

• Digestion begins in the mouth. Our teeth chew food. The food mixes with saliva which makes it easy to swallow.

• The food then passes through the pharynx and the oesophagus down to the stomach.

•The stomach is the widest part of the digestive system. Food mixes in the stom ach with gastric juices.

• The small intestine is a long thin tube. The liver and the pancreas send juices into the small intestine where digestion finishes. The nutrients then enter the blood.

• The large intestine 'is wider than the small intestine. It receives the food that we do not digest. It uses water to change this food into faeces. The faeces then leave the body

through the anus.

The excretory system ANAYA Basic Competences (pages 12-13)What is the excretory system?

Our bodies eliminate waste substances that are bad for us.

We release carbon dioxide when we breathe.

We eliminate other waste substances in urine and sweat

The excretory system is made up of the urinary system and the sweat glands.

The urinary system

The urinary system is made up of the following organs.

•The kidneys are two organs that are on each side of the spinal column. They remove waste substances from the blood. Together with water, these substances become urine,

• The ureters are two tubes that take water from the kidneys to the bladder.

• The bladder is a bag that stores urine.

• The urethra is a tube that takes urine out of the body.

Sweat glands

We sweat when it is hot or when we do 'physical activity. We produce sweat in sweat glands that are all over our skin.

Sweat leaves the body through small holes called pores. This process 'Is called perspiration.

Sweat 'Is mainly water but it includes waste subtances that we eliminate. Perspiration regulates body temperature.