lecture 13

Question 1

where can gases diffuse easily

Answer 1

within the lungs and the tissues

Question 2

why doesnt oxygen diffuse well in water

Answer 2

because it is a non polar molecule and water is polar

Question 3

ectotherms have what type of metabolic rate

Answer 3

low metabolic rate, low 02 demand, and water is ok (cold blooded animals)

Question 4

ectotherms have no

Answer 4

internal temp regulation

Question 5

endotherms have what type of metabolic rate

Answer 5

high metabolic rate, high 02 demand, need air (warm blooded)

Question 6

endotherms have

Answer 6

internal temp regulation

Question 7

small animals like flatworms have digestive and neurons but no

Answer 7

respiratory system because all cells are within 0.5 distance

Question 8

krogh’s rule

Answer 8

all cells must be within 0.5mm of 02 source

Question 9

what is a limitation to having no respiratory system

Answer 9

they have to stay small because if they get big, the cells will no longer be within that 0.5 distance

Question 10

large respiratory surfaces

Answer 10

surface for diffusion and gas exchange

Question 11

what are the respiratory surfaces for water and air breathers

Answer 11

water: gills air: lungs

Question 12

what do these large respiratory surfaces optimize 2 things

Answer 12

they optimize the fick equation by 1. increase surface area which allows more diffusion 2. decrease the distance so these surfaces are as thin as possible causes INCREASE DIFFUSION RATE AND FASTER DELIVERY RATE

Question 13

fish have gills allowing what three things

Answer 13

high surface area, high ventilation, high perfusion

Question 14

ventilation

Answer 14

water movement in one direction over the gills

Question 15

perfusion

Answer 15

highly organized blood vessels allows gas exchange

Question 16

blood that passes by the gills, leaves

Answer 16

oxygenated

Question 17

as blood and water are in contact, oxygen will diffuse from

Answer 17

high partial pressure to low partial pressure

Question 18

fish have what type of gas exchange

Answer 18

countercurrent gas exchange

Question 19

countercurrent gas exchange

Answer 19

water enters in the opposite direction that blood is flowing and causes the deoxygenated blood to face deoxygenated water but theres still enough partial pressure for the diffuse of oxygen to occur. as the water moves right, the partial pressure is getting smaller but still enough to move gases (most in animal kingdom)

Question 20

concurrent gas exchange

Answer 20

water enters at the same side as the blood, and o2 meets with the deoxygenated blood and this causes massive partial difference so lots of 02 moves into blood but as water moves in one direction, oxygen is given off and the difference gets smaller and smaller until it reaches equilibrium

Question 21

how do insect breathe

Answer 21

they have a series of branching air tubules in their bodies called tracheae that are not ventilated nor perfused, they branch until theyre 0.5 away from cells, air just diffuse

Question 22

for the way that insect breathe, they dont need

Answer 22

circulatory systems

Question 23

most air breathing vertebrate use

Answer 23

tidal ventilation

Question 24

tidal ventilation

Answer 24

active breathing , air flows in and out the same path (not unidirectional) and air mixes at respiratory surfaces

Question 25

what occurs to partial pressure when we inhale and exhale

Answer 25

when we inhale we have full partial pressure but as it reaches the respiratory surface to meet blood, it losses that full partial pressure (100->60)

Question 26

why is losing the full partial pressure not an issue for us

Answer 26

we have air readily accessible compared to fish who live in water

Question 27

alveoli

Answer 27

structures with high surface area with very thin epithilium where diffusion of oxygen occurs

Question 28

how do lungs and gills help increase gas diffusion

Answer 28

by increasing area and decreasing distance

Question 29

what type of gas exchange process do birds use

Answer 29

they use both countercurrent gas exchange and air breathing which includes unidirectional air flow, high perfusion, and can deal with low partial pressure NO TIDAL FLOW

Question 30

how do birds breathe

Answer 30

1. air flows into the trachea then into the posterior air sac or the respiratory surface (the air that enters divides) 2. as air flows into the respiratory surface (parabronchi) blood flows the other direction (good partial pressure) 3. exhalation occurs from the posterior air sacs to trachea.

Question 31

birds have what same two things mammals do

Answer 31

shory diffusion distances and large surface areas

Question 32

small animals are able to diffuse gases

Answer 32

directly to cells and the environment

Question 33

bigger animals rely on

Answer 33

perfusion and ventilation

Question 34

most terrestrial animals use

Answer 34

tidal flow through lungs