Module 5: Respiratory System

Question 1

what is minute ventilation

Answer 1

amount of air exchanged (in and out) in one minutes

Question 2

what is alveolar ventilation

Answer 2

amount of tidal volume reaching alveoli

Question 3

what is perfusion

Answer 3

the supply of blood in the lungs. total volume is 500ml

Question 4

what happens in the systemic circulation if there is high carbon dioxide

Answer 4

capillaries with high CO2 stimulates arterioles to dilate, increase blood supply to capillaries

Question 5

what happens in pulmonary circulation when there is high CO2

Answer 5

high CO2 in capillaries stimulates arterioles to constrict, reduce blood supply to capillaries

Question 6

how is forced different to quiet breathing in terms of muscles involved

Answer 6

only diaphragm contracts in quiet breathing, external (inhalation and internal (exhalation) intercostals also involve in forced breathing

Question 7

how is forced different to quiet breathing in terms of energy cost

Answer 7

energy cost lower in quiet breathing, fewer muscles used exhalation passive in quiet breathing

Question 8

in inhalation and exhalation does the atmospheric pressure change

Answer 8

no

Question 9

what is needed to move air into the lungs (alveolar pressure)

Answer 9

alveolar pressure needs to decrease relative to atmospheric

Question 10

what is needed for exhalation (alveolar pressure)

Answer 10

alveolar pressure needs to increase relative to atmospheric pressure

Question 11

how much of the inhaled air reaches the alveoli per breath

Answer 11

tidal volume - airway volume

Question 12

what happens if minute ventilation increases (O2 and CO2)

Answer 12

increases oxygen intake, increase CO2 excretion

Question 13

what does O2 do

Answer 13

diffuses into cell, diffuses into mitochondria, used in mitochondria

Question 14

what does CO2 do

Answer 14

produced in mitochondria, diffuses out, diffuses out of cell

Question 15

diffusion of gas is proportional to

Answer 15

pressure differences between two areas, surface area, solubility of molecule

Question 16

which is more soluble CO2 or O2

Answer 16

CO2 more soluble

Question 17

which has higher pressure CO2 or O2

Answer 17

O2

Question 18

what is haemoglobin to oxygen

Answer 18

an oxygen carrier/buffer

Question 19

difference in haemoglobin in arterial and venous

Answer 19

arterial haemoglobin has 4 oxygens while venous usually has 3

Question 20

when tissues are metabolically active they produce more

Answer 20

CO2, heat, acid

Question 21

Why is Co2 produced

Answer 21

to break down carbs, fats and to regenerate ATP

Question 22

what is CO2 carried as in blood

Answer 22

bicarbonate

Question 23

how is bicarbonate produced

Answer 23

reaction catalysed by carbonic anhydrase in red blood cells. H+ dissociates from H2CO3 to form HCOc-

Question 24

in tissues what produces ATP and CO2

Answer 24

metabolism

Question 25

What happens to CO2 in tissues

Answer 25

it diffuses from tissues to blood where most of it is converted to bicarbonate

Question 26

what happens if H+ is increased (pH decreases)

Answer 26

bicarbonate binds acid to increase pH, then forms water and CO2, increased ventilation removes excess CO2

Question 27

what happens If H+ decreases (pH increases)

Answer 27

reduced ventilation, increase blood CO2

Question 28

what receptors detect CO2

Answer 28

central receptors

Question 29

what receptors detect O2

Answer 29

peripheral receptors