Cardiovascular and Respiratory

Question 1

how are the lungs adapted for gas exchange?

Answer 1

-large surface area allows faster diffusion rates
-thin walls ensuring diffusion remains short
-good ventilation so diffusion rates can be maintained
-good blood supply to maintain high concentration gradient

Question 2

what is the role of the ribs?

Answer 2

-surround and protect the lungs
-aid breathing (move up and down/in and out)

Question 3

what is the role of the diaphragm?

Answer 3

-helps change volume of thorax to allow inhalation and exhalation

Question 4

what is the role of the trachea?

Answer 4

-windpipe that connects mouth and nose
-produces mucus which is moved by the ciliated cells

Question 5

what is the role of the bronchus/bronchi?

Answer 5

-large tubes branching off trachea with one bronchus for each lung

Question 6

what is the role of the bronchioles?

Answer 6

-bronchi split to form smaller tubes in the lungs, connected to the alveoli

Question 7

what is the role of the alveoli?

Answer 7

-tiny moist air sacs, where gas exchange takes place
-each alveolus is covered with capillaries

Question 8

what are the features of the right side of the heart?

Answer 8

-pulmonary artery
-vena cava
-right atrium
-valve
-ventricle

Question 9

what are the features of the left side of the heart?

Answer 9

-aorta
-pulmonary vein
-left atrium
-valve
-ventricle

Question 10

what is the pathway of blood through the heart?

Answer 10

1. deoxygenated blood enters via the vena cava, emptying into the right atrium
2. flows down the valves into the right ventricle
3. ventricles contract, blood travels through the pulmonary artery to the nearby lungs
4. oxygenated blood enters via the pulmonary vein, emptying into the left atrium
5. flows down valves into the left ventricle
6. ventricles contract blood travels through the aorta and to the rest of the body

Question 11

what are some adaptations of the heart?

Answer 11

-left ventricle wall is thicker as it has to pump blood to the whole body
-two sets of valves prevent back flow of blood
-septum prevents the mixing of oxygenated and deoxygenated blood

Question 12

what are the 3 types of blood vessels?

Answer 12

arteries - transport blood away from the heart
veins - transport blood to the heart
capillaries - links arrives to the veins within the tissue of the body

Question 13

what are features of the arteries?

Answer 13

-blood will be at high pressures
-need to be strong and elastic
-thick layer of muscle tissue for strength / elastic to stretch
-wall is thick compared to the lumen

Question 14

what are features of the capillaries?

Answer 14

-really small
-exchange substances of cells
-take away waste products
-walls are single cells thick (and permeable)

Question 15

what are the features of the veins?

Answer 15

-biggest lumen
-thin walls (small layer of elastic and fibres + smooth muscle)
-transports blood back to the heart (walls don’t need to thick)
-valves which prevent backflow