Ch. 13 Part 1 (Book)

Question 1

there is a lot of free O2 in the air, but in water…

Answer 1

only a small amount is dissolved

a lot of CO2 is dissolved though

Question 2

2 ways O2 is transferred btw atmosphere and water

Answer 2

turbulence

diffusion

Question 3

does the solubility of O2 in water decrease as temp and salinity increase?

Answer 3

yes

Question 4

O2 is added to water as __________ is carried out by aquatic plants and algae

Answer 4

photosynthesis

Question 5

how are O2 and CO2 transferred across the body surface

Answer 5

by diffusion

high surface area to volume ratio and low distrance traveled is good

Question 6

respiratory epithelium

Answer 6

specialized respiratory surface made of thin cells

Question 7

_________ systems have evolved to transfer O2 and CO2 via blood flowing betwen the respiratory epithelium and tissues

Answer 7

circulatory

Question 8

how does the circulatory system work in relation to gas exchange

Answer 8

blood passes through a capillary network in a thin film beneath the gas-exchange surface

minimizes distance gases have to diffuse through

maximizes surface area

Question 9

4 basic steps of gas exchange

Answer 9

beathing - supplies the lungs/gills

diffusion of O2/CO2 across respiratory epithelium

bulk transport of gases by blood

diffusion of O2/CO2 across capillary walls in tissue

Question 10

hemoglobin

Answer 10

respiratory pigment that binds O2

increases carrying capacity of blood

Question 11

antarctic icefish

Answer 11

has no respiratory pigment and low O2 content

compensates with a high blood volume and cardiac output

Question 12

structure of hemoglobin

Answer 12

4 iron-containing heme groups

globin tetrametic protein

2 aB dimers

Question 13

positive cooperativity in hemoglobin

Answer 13

binding of 1 O2 makes binding of other O2s easier

O2 bound = oxyhemoglobin

O2 unbound = deoxyhemoglobin

Question 14

myoglobin

Answer 14

respiratory pigment in muscle

high O2 affinity = not good at releasing –> hyperbolic curve

Question 15

is affinity of hemoglobin for carbon monoxide higher than affinity for O2?

Answer 15

yes, 200x higher

carboxyhemoglobin

Question 16

features of hemoglobin O2 transport in blood

Answer 16

at low pO2, low O2 is bound to hemoglobin

at high pO2, a lot of O2 is bound to hemoglobin

sigmoidal curve from pos. cooperativity

high pO2 in lungs = a lot of bound O2 –> low pO2 in muscle = release of O2 into muscle

Question 17

sickle cell anemia

Answer 17

sickle shaped RBC can’t pass through capillaries

impaired O2 delivery

malaria resistance

Question 18

Bohr effect

Answer 18

low blood pH makes hemoglobin O2 affinity lower

release more O2 into tissues

Question 19

what other states lower hemoglobin O2 affinity

Answer 19

high temp

high CO2

hemoglobin binding DPG

Question 20

at high altitude what happens to O2 in the air

Answer 20

there is less O2 –> low blood O2 levels

Question 21

what does a low blood O2 level stimulate in humans

Answer 21

more breathing

higher DPG levels

Question 22

do hemoglobins change during development?

Answer 22

yes, fetal hb binds O2 more tightly to facilitate transfer of O2 from mother to fetus

has gamma chains instead of beta chains

Question 23

CO2 diffuses into the _______ from the ________

Answer 23

blood, tissues

Question 24

from the blood, CO2 _______ across the respiratory surface and is…

Answer 24

diffuses, deposited into the environment

Question 25

CO2 + H2O –>

Answer 25

CO2+ H2O –> H2CO3 –> H+ + HCO3- –> CO32- + H+

CO2 to carbonic acid to bicarbonate to carbonate ions

Question 26

CO2 + OH- –>

Answer 26

CO2 + OH- –> HCO3-

Question 27

__________ is the predominant form of CO2 in the blood at normal pH

Answer 27

bicarbonate

Question 28

carbamino compounds

Answer 28

protein-NH2 + CO2 –> H+ + protein-NHCOO-

Question 29

does CO2 enter and leave the blood as CO2 or HCO3-

Answer 29

CO2 b/c it diffuses through membranes much faster than HCO3- ions

Question 30

carbonic anhydrase

Answer 30

enzyme that catalyzes CO2 + OH- –> HCO3-

Question 31

most CO2 entering and leaving the plasma….

Answer 31

done by RBC b/c they have carbonic anhydrase

Question 32

chloride shift

Answer 32

when HCO3- ions leave RBC, Cl- ions enter the RBC via band III protein to maintain ion balance

Question 33

Haldane effect

Answer 33

deoxygenation of Hb in tissues reduces pH as Co2 enters the blood

Question 34

where is carbonic anhydrase in the lungs

Answer 34

in the endothelial cell membranes

so HCO3- can be converted to CO2 fast as blood perfuses the lung capillaries