Concepts 7.1-7.3 (Physiology)

Question 1

What is the main difference between aerobic and anaerobic respiration?

Answer 1

Aerobic respiration requires oxygen and anaerobic respiration requires no oxygen (or very little)

Question 2

Which type of respiration releases more ATP molecules?

Answer 2

Aerobic

Question 3

What are the 3 stages of aerobic respiration?

Answer 3

glycolysis, the Kreb’s cycle, oxidative phosphorylation

Question 4

What are the 2 main processes in anaerobic respiration?

Answer 4

glycolysis and fermentation

Question 5

How does diffusion of respiratory gasses work?

Answer 5

High to low concentration

Question 6

What does a large SA:V ratio do?

Answer 6

Speed up the rate of exchange

Question 7

What do very thin exchange surfaces do?

Answer 7

Keep the diffusion pathways short

Question 8

What does a partially permeable membrane do?

Answer 8

Allow selected materials to diffuse easily

Question 9

What does the movement of external medium (e.g. air) do?

Answer 9

Maintains a diffusion gradient

Question 10

What does the movement of an internal medium (e.g. blood) do?

Answer 10

Maintain a diffusion gradient

Question 11

Where does gas exchange primarily occur in plants?

Answer 11

The stomata

Question 12

How do different plants types regulate gas exchange

Answer 12

Different shapes of stomata and presence of guard cells

Question 13

How does O2 and CO2 diffuse rapidly through plants?

Answer 13

Intercellular air spaces, which drive pressure gradients

Question 14

How do fungi undertaken respiration?

Answer 14

Diffusion across their cell and body walls via mycelium
- Also switch between aerobic and anaerobic respiration

Question 15

How do animals in aquatic environments with thin tissues avoid specialise structure for gas exchange?

Answer 15

Oxygen diffusion across their body wall

Question 16

What are the two main types of gas exchange structures for larger organisms?

Answer 16

ventilation and circulation

Question 17

How do small terrestrial animals respire?

Answer 17

Trachea - large surface area

Question 18

How do gills work?

Answer 18

Oxygen diffuses from water into the blood within the gill capillaries

Question 19

What features of gas exchnage surface maximise gas exchange?

Answer 19

• Membrane area (SA)
• Pressure gradient
• Solubility
• Molecular weight

Question 20

What happens to stomatal density as temp increases?

Answer 20

Increases
(coz resp rate increases)

Question 21

What happens to stomatal density as CO2 concentration increases?

Answer 21

decreases
(coz don’t want concentration higher than outside plant)