transportation in animal

Question 1

what substances is there in blood and their function

Answer 1

red blood cells - transport oxygen. It contains haemoglobin so that it can pick up oxygen and let go. It had no nucleus so more space for haemoglobin

phagocytes - remove any microorganism that invades the body. irregular nucleus allows to squeeze through gaps in the wall of capillaries

lymphocytes - produce antibodies to help in the defence against diseases. A large nucleus allows having many copies of genes

platelets - for blood clotting.

plasma - carries dissolved food molecules, waste materials, and hormones

Question 2

what kind of blood circulation do humans have and why

Answer 2

double circulation, the blood passes through the heart twice for each complete circuit of the body.

Question 3

feature and adaptation of artery

Answer 3

a thick outer wall, narrow tube, a thick layer of muscle. smooth lining so no obstruction to flow of blood.

carries blood away from the heart
blood is at high pressure
blood is rich in oxygen

Question 4

feature and adaptation of vein

Answer 4

a thin outer wall, wide tube, thin layer of muscle. presence of valve

carries blood to the heart
blood is at low pressure
blood is low in oxygen
valve prevents the backflow of blood

Question 5

disadvantage of single circulation

Answer 5

pressure too low for efficient kidney function

Question 6

feature and adaptation of capillaries

Answer 6

capillaries are only one cell thick

enormous surface area

Question 7

process of blood flow in the heart

Answer 7

blood enters the heart through vena cava
enters right atrium
going through the right atrioventricular valve enters the right ventricle
going through the semilunar valve, enter pulmonary arteries
enter lungs
come back to the heart by pulmonary vein
enters left atrium
going through the left atrioventricular valve, enter the left ventricle
going through semilunar valve, go to aorta

Question 8

what is the wall in the middle in the heart that is dividing right and left ventricle

Answer 8

septum

Question 9

which wall is thicker, left or right ventricle

Answer 9

wall of left ventricle

Question 10

what might cause coronary heart disease

Answer 10

poor diet, lack of exercise, genetic factors

Question 11

which surgery can help to coronary heart disease, and how

Answer 11

Angioplasty

a metal cage widen the narrowed artery allow blood to flow more easily