Revision Quiz 7: Chapter 8 - Transport in Mammals

Marks scored: 32/55
hehe... no real BAD comments this time =p since I passed XD hehe... So... here are the answers for last weeks quiz!

1 The heart is made of cardiac muscles. If functions as a pump. It is completely separated into right a left halves by a median septum.

2 The heart needs a constant supply of glucose/food/nutrients and oxygen in order to carry out its pumping action. These are supplied to it via blood vessels known as the coronary arteries. If these arteries are blocked by fatty deposits, oxygen cannot reach the heart muscles. They will degenerate giving rise to coronary heart diseases.

3 The left side of the heart receives oxygenated blood from the lungs and pumps it to the rest of the body via aorta. These blood vessels are highly muscular to withstand the high pressure of blood flow. This is systemic circulation.

4 The right side of the heart receives deoxygenated blood from the rest of the body via vena cava and pumps it to the lungs. These blood vessels contain valves that prevent backflow of blood. This is pulmonary circulation.

5 Oxygen and nutrients first diffuse into the tissue fluid from the blood before entering the body cells. Waste products excrete out of the body cells into this fluid before diffusing into the blood/plasma/capillaries.

6 List FIVE materials transported by the blood.

I wrote: iron, oxygen, carbon dioxide, glucose, platelets

Other possiblities are: amino acids, fatty acids, glycerol, soluble proteins, waste products, hormones, urea, minerals, red blood cells, white blood cells.

Waste products ---> urea, carbon dioxide
Nutrients ---> glucose, amino acids, fatty acids, glycerol
*FOR MARKING: Only main group OR individual material e.g. Waste products and carbon dioxide cannot be placed together in answer.

7 Name
a) the fluid part of the blood; plasma

b) the cells found in the blood; red blood cells + white blood cells

8 Describe the origin of platelets and their function.
- Platelets are fragments of cytoplasm from certain bone marrow cells
- They are required in blood clotting

9 Name the chambers of the heart
- Right atrium
- Right ventricle
- Left atrium
- Left ventricle

10 Name the valves in the heart, stating their site of action and function.

Name              Site of action
tricuspid valve   Between right atrium & ventricle
bicuspid valve    Between left atrium & ventricle
semilunar valves  In vena cava, pulmonary ventricle
                  & aorta

Function of valves: to prevent backflow of blood