Intro to CO2 and O2 Physiology

Question 1

Aquatic animals take up dissolved oxygens using gills. Two prime examples are

Answer 1

Coral reef worms 
Diving beetles (bubbles)

Question 2

T or F: Does Oxygen use active transport?

Answer 2

False

Question 3

How do reefworms transport oxygen?

Answer 3

Elaborate circulatory system filled with blood rich in hemoglobin oxygen transport pigment. As blood flows through gill tentacles, oxygen enters blood via passive diffusion.

Question 4

How do diving beetles transpot oxygen?

Answer 4

Use a bubble that serves as a gill. While submerged, oxygen moves steadily into the bubble. Oxygen is distributed to cells by entering tracheal system

Question 5

What are the respiratory gases?

Answer 5

Oxygen and Carbon Dioxide

Question 6

How do respiratory gases move?

Answer 6

Via simple diffusion and convection (bulk flow)

Question 7

Chemical potential dictates that

Answer 7

1. A solute diffuses from high to low conc.

2. Rate of diffusion is proportional to its difference in concentration between regions

Question 8

What is the Law of Partial Pressures?

Answer 8

The total pressure exerted by a mixture of gases is the sum of individual pressures exerted by each of the several component gases in the mixture; expressed as a fraction

Question 9

What is the universal gas law?

Answer 9

Calculates partial pressure of each gas in a mixture

PV=nRT

Question 10

Partial pressure and concentration of any gas are simply proportional to each other at ____

Answer 10

any given T

Question 11

Air with oxygen at 0.21 atm and oxygen-free water, what will happen?

Answer 11

Oxygen will dissolve in water to reach equilibrium

Partial pressure of oxygen in aqueous solution will be 0.21 atm

Question 12

What is Henry’s law?

Answer 12

Relates partial pressure and concentration in aqueous solutions.
Cx=APx
(Cx- dissolved conc of gas, A-absorpion coefficient, Px- partial pressure)

Question 13

Henry’s law only works if

Answer 13

1. Solubilities of the gases are different
2. Solubility of gases in aqueous solution decrease with inc water temp
3. Solubility decreases with increasing salts

Question 14

If you have a gas mixture with uniform temperature and uniform salinity (salts) what will happen?

Answer 14

Gas will diffuse from both high to low partial pressure and high to low concentration

Question 15

How do scuba divers regulate pressures?

Answer 15

Scuba air regulator ensures air in lungs is at pressure equal to environmental water pressure at that depth

Question 16

If a scuba diver rises too quickly, what happens?

Answer 16

High N2 partial pressure will force macroscopic bubbles to form in blood

Question 17

True or false: Gases diffuse slower in gas than in aqueous solutions

Answer 17

False. They diffuse faster.

Question 18

How large of a distance must exist for diffusion in water to meet O2 requirements of living tissues

Answer 18

< 1 mm

Question 19

Why don’t you want water in your lungs?

Answer 19

Accumulation of fluid in the lungs creates a small diffusion distance that is tolerable with water present

Question 20

How do sea turtle eggs work?

Answer 20

Eggs are buried deep into the sand and rely on O2 diffusion through sand. If eggs are buried too close to shore and become submerged in water before hatching, the eggs will die.

Question 21

How do Anchovy Larvae work?

Answer 21

They have an undeveloped circulatory system and depend on O2 diffusion from body surfaces. They will die if there is low O2 in the water.

Question 22

How does hemoglobin effect diffusion rate?

Answer 22

When O2 diffuses from environment to blood, O2 mlcs that combine with hemoglobin do not increase blood’s partial pressure of O2. Therefore O2 molecules with hemoglobin do not interfere with further O2 diffusion into blood.

Question 23

Define convection

Answer 23

Transport by bulk flow

Question 24

When does convection occur?

Answer 24

When gas mixture or aqueous solution flows and gas molecules in the gas or liquid are carried from place to place by the fluid flow

Question 25

Is convection faster or slower than gas diffusion?

Answer 25

Faster. It depends on forced fashion, not random molecular movements.

Question 26

What are the rewards and requirements of breathing and pumping blood?

Answer 26

Requires metabolic energy

Reward speed up transport of O2 + CO2

Question 27

Explain prairie dogs and burrows?

Answer 27

They construct burrows in a way that wind flowing parallel to the ground surface to renew O2 supplies underground through burrows

Question 28

What are the flow types?

Answer 28

1. Unidirectional (blood through blood vessel)

2. Tidal flow (in and out)

Question 29

What is the oxygen cascade?

Answer 29

Summarizes O2 transport from environment to mitochondria.

Ambient air -> alveolar gas -> arterial blood -> systemic capillary blood -> mitochondria

Question 30

Describe the respiratory environment

Answer 30

Gases are exchanged with adjacent regions by diffusion and convections, evening out partial pressures of O2 and CO2

Question 31

Describe photosynthetic organisms in the day

Answer 31

Add O2 to air/water and extract CO2

Question 32

Describe photosynthetic organisms at night

Answer 32

Remove O2 and add CO2

Question 33

Animals, bacteria and fungi remove ___ and add ____

Answer 33

O2 and add CO2