Respiratory

Question 1

partial pressure

Answer 1

gas exchange moves by diffusion only so needs differences

Question 2

Solution for slow diffusion of gases

Answer 2

increase surface area of gas exchange

Question 3

Solution for partial pressure drop off with square distance

Answer 3

reduce distance gases must travel with oxygen carrying cells

Question 4

Insects

Answer 4

air-filled branching network of tubes and tracheoles, limits size of organism

Question 5

Carboniferous period

Answer 5

300 million years ago oxygen in atm was much greater (35%) meaning larger insects

Question 6

gills

Answer 6

increase surface area for gas exchange under water

Question 7

counter current exchange

Answer 7

water flows directly over capillary beds in gills of fish in opposite direction of blood flow

Question 8

amphibians

Answer 8

exchange gas through skin and lungs, creating positive pressure to force air into lungs

Question 9

birds

Answer 9

air moves in one direction so inhaled air does not mix with exhaled air

Question 10

trachea

Answer 10

stiff, large tube that maintains an open passage, enters the thoracic cage and divides into two bronchi

Question 11

Bronchi

Answer 11

connect trachea to lung

Question 12

bronchioles

Answer 12

smaller branches of bronchi wrapped in smooth muscle

Question 13

alveoli

Answer 13

sacs at end of bronchioles covered in capillaries for gas exchange

Question 14

surfactant

Answer 14

phospholipids and proteins the reduce surface tension of water but still keep lungs moist and able to inflate

Question 15

pressure gradient

Answer 15

air will move from high pressure
to low pressure

Question 16

compressing a gas

Answer 16

pressure will go up

Question 17

expanding a gas

Answer 17

pressure will go down

Question 18

inhalation

Answer 18

diaphragm contracts and moves down –> vol of lungs increased –> pressure in lungs low, air moves in

Question 19

exhalation

Answer 19

diaphragm relaxes and moves up –> vol of lungs decreases –> pressure in lungs high, air moves out

Question 20

Transpulmonary pressure

Answer 20

pleural cavity pressure lower than pressure in lungs, keeping them inflated

Question 21

collapsed lung

Answer 21

thoracic cavity punctured, losing pressure differential

Question 22

dead space

Answer 22

trachea and bronchioles that do not participate in gas exchange

Question 23

control of respiration

Answer 23

CO2 levels monitored through pH by the medulla

Question 24

pressures entering alveolar capillaries

Answer 24

high PCO2 and low PO2 since returning from body tissues

Question 25

pressures in alveolar space

Answer 25

high PO2 and low PCO2 (Lower than atm due to dead space)

Question 26

alveoli gas exchange

Answer 26

O2 moves into blood and CO2 into alveolar space

Question 27

pressures entering systemic capillaries

Answer 27

high PO2 and low PCO2 (just experienced gas exchange)

Question 28

pressures in interstitial fluids of tissues

Answer 28

high PCO2 and low PO2 (cellular metabolism uses up oxygen and produces CO2)

Question 29

body tissue gas exchange

Answer 29

O2 moves into tissues and CO2 moves into blood

Question 30

erythrocytes

Answer 30

red blood cells with high O2 carrying capacity due to hemoglobin

Question 31

hemoglobin

Answer 31

binds to 4 oxygen with increasing affinity until saturated (P =100mm), and dissociates in low pressures (P= 40mm)

Question 32

carbonic acid

Answer 32

water-soluble version of CO2 for transport

Question 33

carbonic anhydrase

Answer 33

enzyme in erythrocytes that converts CO2 to carbonic acid, or reverse