Gas Exchange

Question 1

Why is water a harder respiratory medium than air

Answer 1

Oxygen solubility is lowest in seawater.
Carbon dioxide is more soluble
oxygen solubility decreases when salinity increases

Question 2

Ventilation strategies

Answer 2

Unidirectional, entry and exit
Tidal, in and out
nondirectional

Question 3

Fick’s Law

Answer 3

Rate of Diffusion=k(diffusion constant) x SA x (P2-P1)

Question 4

Echinoderms GE

Answer 4

Across epithelium of branchial papillae of tube feet, more complex in holothurians.

Question 5

Polychaetes GE

Answer 5

Gills along the body with cilia

Question 6

Molluscs GE

Answer 6

Diverse systems. Mantle overhangs part covering the internal gills.

Question 7

Crustacea GE

Answer 7

Water outward through exhaling opening down a pressure gradient.

Question 8

Fish GE

Answer 8

Gills. Arch supports gills, racers are on the front of the arch and filaments trail along the arch.

Question 9

Sharks GE

Answer 9

Bottom dwelling species have spiral;es so water is forced into the buccal cavity. Without them they cannot stop moving.

Question 10

bimodal fish

Answer 10

Low oxygen environments, air bubble in gill chamber. Secondary use of swim bladder, some have true lungs.

Question 11

Aerobic and anaerobic production

Answer 11

Aerobic 38 ATP
Anaerobic 2 ATP, glycolysis

Question 12

Hypoxia responses

Answer 12

Low oxygen after eutrophication. Species can decrease metabolic needs, so less oxygen used. Also rely on anaerobic respiration

Question 13

Measuring metabolic rate

Answer 13

Direct, heat calorimeter, difficult and expensive.
Indirect, difference between in and out. Open, closed, intermittent, bimodal intermittent.

Question 14

Metabolic rate factors

Answer 14

Cal/time
Activity intensity, temperature, sex, gender diet, lifestyle, size, reproduction.

Question 15

Field metabolic rate

Answer 15

Free-roaming animal