gas exchange

Question 1

why do organisms need a respiratory system?

Answer 1

• cellular respiration
  - transformation and chemical energy into ATP
• photosynthesis
• remove carbon dioixde

Question 2

what is required for a gas exchange?

Answer 2

• respiratory medium
• large surface area
• respiratory surface
• moist
• thin and freely permeable to gases

Question 3

what are the advantages of gas exchange on land?

Answer 3

○ Higher concentration of CO2
○ O2 and CO2 diffuse much faster through air
○ Air is much lighter than water and therefore easier to pump
§ Expend less energy moving air in and out

Question 4

what are the disadvantages of gas exchange on land?

Answer 4

○ Keep large respiratory surface moist causes high water loss
Reduce water loss by keeping lungs internal

Question 5

what are the terrestrial adaptations?

Answer 5

• Tracheae
○ Air tubes branching throughout the body
○ Gas exchange be diffusion across moist cells lining terminal ends, not through open circulatory system

Question 6

what are the gaseous exchanges in plants?

Answer 6

stomata (leaves)
stem (lenticels)
root (root hair)

Question 7

what are the factors influencing gas exchange?

Answer 7

the amount of oxygen required for respiration is determined by:

• amount of living cells in the organisms (size)
• rate at which the cells are respiring (metabolic rate and activity)