3.1 Exchange surfaces and breathing

Question 1

A big animal has a …….. SA:V

Answer 1

small

Question 2

A small animal has a ……… SA:V

Answer 2

big

Question 3

What 3 factors affect the need for an exchange system?

Answer 3

size
SA:V
level of activity

Question 4

What are features of a good exchange surface?

Answer 4

large SA:V
a thin barrier
a good blood supply

Question 5

What are the 4 main parts to the mammalian gaseous exchange system?

Answer 5

Trachea, bronchi, bronchioles, and alveoli

Question 6

How does the mammalian gaseous exchange system have a large SA:V?

Answer 6

millions of alveoli

Question 7

How is the diffusion distance shortened in the mammalian gaseous exchange system?

Answer 7

Squamous epithelial cells are thin and flat

Question 8

What fibers do alveoli have?

Answer 8

Elastic fibres

Question 9

What do the trachea, bronchi and bronchioles have in common?

Answer 9

goblet cells

Question 10

How are the trachea and bronchi similar in structure?

Answer 10

cartilage (C shaped in trachea)

Question 11

What structure do bronchioles have?

Answer 11

smooth muscle and elastic fibres

Question 12

Why is it useful for smooth muscle to contract or relax?

Answer 12

If there is a harmful substance, it can contract

Question 13

What should you check before using a spirometer?

Answer 13

subject does not have asthma
fresh soda lime
no leaks
mouthpiece sterilised
water chamber not overfilled

Question 14

What is the vital capacity?

Answer 14

The volume of air that can be moved by the lungs in one breath (av. 2.5-5.0 dm^3)

Question 15

What is the residual volume?

Answer 15

The volume left in the lungs after forced expiration approx. 1.5 dm^3

Question 16

What is the tidal volume?

Answer 16

The volume moved in and out with each breath (usually at rest) e.g 0.5 dm^3

Question 17

How are fish gas exchange surfaces specialised?

Answer 17

The gills have lots of lamellae to increase surface area
Countercurrent flow

Question 18

What is the process of ventilation in a fish?

Answer 18

Lower the buccal cavity to increase volume and water rushes in
Mouth closes and buccal cavity raised to push water over the gills and out

Question 19

What is the pore called on the body of an insect?

Answer 19

Spiracle

Question 20

What is the fluid called at the end of tracheoles?

Answer 20

tracheal fluid

Question 21

What happens to the tracheal fluid when the insect is active?

Answer 21

The fluid moves out of the tracheole to increase the surface area of gas diffusion into cells

Question 22

What are the main features of insect ventilation?

Answer 22

an air sac that can contract to push air around the body
wing movement can force air around the body
abdomen movement can force air around the body