Transport in animals

Question 1

circulatory system

Answer 1

system of blood vessels with a pump and valves to ensure one-way flow of blood.

Question 2

In single circulation of fish

Answer 2

The blood passes through the heart once for one
complete circuit. It moves from the heart to the gills and then to the rest of the body.

Question 3

Mammals have double circulatory system

Answer 3

One pulmonary loop and one systematic
loop happens in mammals. Blood passes through the heart twice for one complete
circuit.

Question 4

Advantage of double circulation

Answer 4

high(er), blood pressure / flow rate (than single circulation) ;
allows different blood pressure in each loop ;
prevent mixing of oxygenated and deoxygenated blood ;
allows animals to have high metabolic rates ;
allows animals to be, large / tall ;

Question 5

Blood is pumped away from the heart in

Answer 5

arteries and returns to the heart in veins.

Question 6

The activity of the heart may be monitored by

Answer 6

ECG, pulse rate and listening to
sounds of valves closing.

Question 7

Coronary heart disease is the blockage of

Answer 7

coronary arteries

Question 8

CHD causes

Answer 8

diet, lack of exercise, stress, smoking, genetic predisposition, age and sex.

Question 9

helps to reduce the risk of coronary heart disease

Answer 9

Balanced diet and exercise,They
reduce stress, lower blood pressure, make heart muscles stronger.

Question 10

Atria

Answer 10

receives blood from either the lungs or the body and supply it to the ventricles. The ventricles pump blood out of the heart and all around the body. So pressure applied by the ventricles must be high. To help them do this, the ventricles have much thicker, more muscular walls than the atria.

Question 11

The right ventricle

Answer 11

pumps blood to the lungs, which are very close to the heart

Question 12

The left ventricle,

Answer 12

however, pumps blood to the rest of the body. The left ventricle has an
especially thick wall of muscle to enable it to do this.

Question 13

Septum

Answer 13

separates oxygenated and deoxygenated blood in the heart.

Question 14

As physical activity increases heart rate increase because

Answer 14

muscles contract more.
Muscles require more energy. More aerobic respiration takes place. More oxygen is
required. More blood is required to be transported to muscles for more oxygen.
Heart beats faster to supply more oxygen to the muscles.

Question 15

Arteries:

Answer 15

Have thick walls
The diameter of lumen is small
No valves are present

Question 16

Veins

Answer 16

Have relative thin walls
Diameter of lumen is large
Valves are present to prevent back flow of blood.

Question 17

Blood pressure in arteries is

Answer 17

high because it has just been forced out of the heart by
the contraction of muscles of the ventricles. Arteries need very strong walls to
withstand this high pressure.

Question 18

Blood in arteries doesn’t flow smoothly, it

Answer 18

pulses through. When ventricles contract
pressure in arteries is high and when ventricles relax pressure in arteries is reduced.
Arteries have elastic tissues in their walls which can stretch and recoil with the force
of the blood making the blood flow smoother.

Question 19

Capillaries

Answer 19

very small and penetrate to every part of the body so that they can reach every cell.

Question 20

The function of the capillaries is to

Answer 20

take nutrients, oxygen and other materials to all the
cells in the body, and to take away their waste materials. To do this, their walls must
be very thin so that substances can get in and out of the capillaries easily.

Question 21

Veins function

Answer 21

return blood to the heart.

Question 22

veins adaptation

Answer 22

Walls of veins (muscle and elastic tissue) are thin because there is no need for
strong walls as most of the blood pressure has been lost.
They have a wide lumen because it offers less resistance to blood flow.
Contain valves, that prevent backflow of blood.

Question 23

Components of blood are

Answer 23

red blood cells, white blood cells, platelets and plasma

Question 24

Red blood cells function

Answer 24

transporting oxygen. Haemoglobin is present in RBC and it combines with oxygen transports it.

Question 25

White blood cells function

Answer 25

phagocytosis and antibody production

Question 26

Platelets function

Answer 26

clotting

Question 27

Plasma function

Answer 27

transport of blood cells, ions, nutrients, urea, hormones and
carbon dioxide

Question 28

The roles of blood clotting are

Answer 28

preventing blood loss and prevent entry of pathogens.

Question 29

Lymphocytes have

Answer 29

one big nucleus which covers almost the entire cell. Phagocytes
have a nucleus that divides into small connected balls.

Question 30

Function of lymphocytes

Answer 30

is antibody production