Respiratory System 2

Question 1

In any mixture, pressure exerted by any 1 gas

Answer 1

= total x fractional conc. of that gas in mixture

Question 2

In body normal PP =

Answer 2

47 mmHg

Question 3

Alveolar gas pressures

Answer 3

PO2 = 105 mmHg, PCO2 = 40 mmHg

Question 4

Atmospheric gas pressures

Answer 4

PO2 = 160 mmHg, PCO2 = 0.5mmHg

Question 5

PO2 lower because

Answer 5

O2 enters pulmonary capillaries

Question 6

In tissue, no net diffusion because

Answer 6

intracellular PO2

Question 7

In capillaries as blood flows , pressures of

Answer 7

O2 < PCO2

Question 8

Pulmonary capillaries greatest ___ to ___ at____

Answer 8

resistance, blood flow, rest

Question 9

If increase in _____ blood flow then _____ in resistance in capillaries by recruitment of X and Y

Answer 9

Pulmonary, decrease, closed capillaries and distension of open arms

Question 10

Important factors for gas exchange

Answer 10

1. 2,3 DPG (erthocytes)
2. H+
3. Temp
4. Blood PCO2

Question 11

Central Chemoreceptors are on X and respond to Y

Answer 11

X - ventral surface of medulla

Y - Increase in [H+] by stimulating nearby resp. centre

Question 12

Condition of central chemoreceptor response

Answer 12

PO2 < 60mmHg

Question 13

Chemoreceptors in carotid bodies respond ___

Answer 13

quickly -> a.p. frequency increase

Question 14

How do central chemoreceptors overcome the BBB?

Answer 14

CO2 forms H2CO3 which forms H+ and CO3- in CNS

Question 15

Pulmonary reflexes have receptors in

Answer 15

Tracheobronchial tree + lungs