transport of O2 and CO2

Question 1

transport of O2 is carried in 2 forms

Answer 1

dissolved and bound to hemoglobin

Question 2

dissolved transport of O2

Answer 2

dissolves poorly in plasma
- amount of O2 dissolved is proportional to Po2
- At Po2 of 100 mmHg only 0.3 ml O2/100mL dissolved in blood (only a small amount of O2 is dissolved in blood)

Question 3

each hemoglobin molecules can bind _ O2 molecules

Answer 3

4

Question 4

As PO2 increase, O2 bound to Hb increases but not linear

Answer 4

• as O2 bids to Hb it increases affinity of O2 for Hb, making it easier for the next O2 to binds
• O2 is removed from Hb is decrease the affinity of O2 for Hb, more O2 is removed from Hb

Question 5

O2 bound to Hb does not contribute to

Answer 5

Po2

Question 6

Dissolved O2

Answer 6

defines PO2 - dissolved O2 and PO2 are basically the same thing
detected by chemoreceptors - O2 bound to Hb cannot be detected
used by cells

Question 7

what is O2 bound to Hb used for

Answer 7

storage form of O2, O2 can be removed from Hb to become dissolved O2

Question 8

Po2 = 100 mmHg (Hb curve)

Answer 8

PO2 found in lungs, Hb becomes 100% saturated with O2 in the lungs

Question 9

Po2 = 60 mmHg

Answer 9

PO2 Hb is nearly 100% saturated (there is a safety factor for Hb saturation)

Question 10

Po2 = 40 mmHg

Answer 10

PO2 found as blood flows past TISSUE, Hb 75% saturated, so 25% of O2 removed near tissue

Question 11

Po2 = 25 mmHg

Answer 11

Po2 found near ACTIVE TISSUE, Hb 50% saturated, so 50% removed

Question 12

steep region of the O2-Hb curve is steep because

Answer 12

as O2 is removed the affinity of O2 for Hb decreases making it easier to remove the next O2

Question 13

Bohr effect

Answer 13

O2-Hb curve shift to the right by H+ or CO2

Question 14

shift left of O2-Hb curve is caused by:

Answer 14

decreased H+, CO2, temperature, DPG

Question 15

the shift left occurs in the

Answer 15

lungs
- makes it easier to add O2 to Hb as blood flows through the lungs

Question 16

O2-Hb curve shift to the right is caused by

Answer 16

increased H+, CO2, DPG, Temperature (all produced by active tissue)

Question 17

DPG

Answer 17

produced by RBCs, DPG release is stimulated by hypoxia and exercise

Question 18

shift to the right occurs near

Answer 18

active tissue (makes it easier to remove O2 and deliver it to the tissue

Question 19

decrease of dissolved O2 in arterial blood causes

Answer 19

diffusion impairment (edema in the lungs)
decreased atmospheric Po2 (high altitude)

Question 20

decreased dissolved PO2 will be detected by ____ and stimulate breathing

Answer 20

chemoreceptors

Question 21

no decrease of dissolved O2 in arterial blood but insufficient O2 causes

Answer 21

not enough red blood cells (anemia, less Hb, less O2 bound to Hb)
carbon monoxide (CO) poisoning (CO bound to Hb, less O2 bound to Hb)

Question 22

when dissolved O2 is used, there is no

Answer 22

O2 to remove from Hb to replace it

Question 23

normal PO2 but insufficient O2 in tissues is not detected by

Answer 23

chemoreceptors

Question 24

3 forms of CO2 transport

Answer 24

dissolved in plasma (10%)
bound to proteins (mainly Hb, 30%)
bicarbonate ions (60%)

Question 25

carbonic anyhdrase

Answer 25

enzyme needed to concert CO2 to HCO3-
found in RBCs

Question 26

Haldane effect

Answer 26

when O2 binds to Hb, less CO2 binds to Hb

Question 27

Haldane effect occurs in

Answer 27

the lungs
- O2 diffuses into blood- binds Hb - less CO2 bound to Hb - CO2 expired

Question 28

Bohr effect occurs near

Answer 28

active tissue when there are high levels of CO2 binding to Hb so there is less O2 bound to Hb