Physics of Gas Transport

Question 1

What are the 2 ways to transport oxygen?

Answer 1

1) attached to the hemoglobin

2) dissolved O2 in the blood/plasma

Question 2

what does O2 transfer depend on?

Answer 2

• alveolar O2 tension
• hemoglobin levels
• O2 consumption
• Hemoglobin saturation

Question 3

What is mixed venous oxygen?

Answer 3

the amount of oxygen returning to the right side of the heart. Normally the saturation is 65-75% and O2 pressure is 35-45mmHg.

Question 4

What are the factors that determine how much O2 extracted by tissue?

Answer 4

• Oxygen saturation
• concentration of hemoglobin
• O2 consumption
• Cardiac Output- (helps compensate for low hemomglobin)

Question 5

What is the Fick Equation?

Answer 5

O2 consumption = CO x (CaO2-CvO2)

Question 6

T or F. if the metabolism decreases, then O2 consumption decreases

Answer 6

TRUE

Question 7

What is normal O2 consumption, cardiac output and extraction?

Answer 7

• 250 ml/min
• 5000 ml/min
• 25%

Question 8

T or F. Delivery and Consumption are dependent at low levels

Answer 8

False. They are independent at low levels and have a direct relationship to each other at high levels

Question 9

How much O2 is usually stored and where is all this saved up O2 located?

Answer 9

normal 1500 ml

• bound to hemoglobin
• remaining in lungs
• dissolved in body fluids

Question 10

what is the physiology of hemoglobin?

Answer 10

a large protein molecules that is made up of 4 subunits with Fe in the middle. The Fe is able to change so it is able to take up oxygen. Each subunit can carry one O2

Question 11

What are the factors for oxygen dissociation from hemoglobin?

Answer 11

• 2,3-diphosphoglycerate
• CO2 tension
• H+ ion concentration
• temperature

Question 12

What 2,3-diphosphoglycerate

Answer 12

It is located in the hole of the hemoglobin protein molecule and it allows change in the hemoglobin to load and release oxygen

Question 13

T or F. As temperature cools, metabolic rates go down, affinity for oxygen becomes stronger

Answer 13

TRUE. This causes a left shift in oxygen dissociation curve

Question 14

T or F. when an area of the body becomes more acidic, more O2 is released from hemoglobin in this area

Answer 14

TRUE. This causes a right shift in oxygen dissociation curve

Question 15

What are the classifications of hypoxia?

Answer 15

Hypoxic - 5 categories (V/Q mismatch, shunt, etc.)
Cardiac - low perfusion
Hemic - low hemoglobin
Demand - increase in consumption
histotoxic - cell usage

Question 16

what are the 3 ways CO2 is transported?

Answer 16

• dissovled in plams
• bicarbonate
• carbamino compounds

Question 17

which is the primary way to transport CO2

Answer 17

When CO2 mixes with water to make carbonic acid