The Circulatory System

1.           Why is blood important? What happens to oxygenated blood after it leaves the lungs?

The blood carries the oxygen to all parts of our body.

The heart pumps the oxygenated blood to every part of the body.

2.         Why does blood move around the body? What are the two routes of blood circulation?

Because every cell in the body receives oxygen and nutrients from blood.

The two routes of blood circulation are: pulmonary circulation and Coronary circulation.

BLOOD

3.         What are the components of blood? What do platelets do?

The mains components are plasma, red blood cells, white blood cells and platelets.

Blood platelets are very small cells which make blood coagulate when it is not in closed blood vessels.

The heart

4.         Why is the heart important? What parts are inside the heart? Do you remember the names of the most important artery and vein?

The heart is important because it pumps blood. There are two atrium and two ventricles. The aorta and vena cava.

5.         What is the heart?

The heart is a hollow muscular organ. It pumps blood around the body through arteries, veins and capillaries.

6.         What are the names of the hollow spaces inside the heart?

The hollow space inside the heart is divided into two atriums. They received blood from veins.

7.         How does blood circulate inside the heart?

Blood goes from the heart to the lungs, from the lungs goes back to the heart and then it goes to the body.

SCIENCE

UNIT 1 NUTRITION

1.   What nutrients do our bodies need?

Carbohydrates, fats, proteins, vitamins and minerals.

2. Do we use all the food that we eat?

No, we don’t. We eliminate other substances we don’t need by the excretory and the digestive.

3. What are the organs in the digestive system?

Mouth, salivary glands, pharynx, oesophagus, stomach, small intestine, liver, pancreas, large intestine, appendix, rectum, anus.

4. What do we need food for?

Food provides us with the nutrients we need.

5. What does our body do with food in our stomach?

The stomach squeezes and mixes food with juices.

6. Why do we mix food with saliva?

Because saliva, contains an enzyme. The enzyme helps break the food into pieces.

7. What is absorption and where do the nutrients enter the blood?

During the process of absorption, the nutritional substances enter the blood vessels through the thin walls of the small intestine. Now blood can carry nutrients around the body.

8. How many teeth have we got?

Children have 20 first (or milk) teeth. From about the age of six, 32 permanent teeth.

9. What is digestion?

The physical process that changes food into nutrients.

10. What is the function of saliva?

The saliva contains an enzyme which helps break the food into pieces.

   11. What does the small intestine do?

The small intestine has thin walls and nutritional substances enter the blood vessels through these walls. We call this process absorption.