misc gas exchange ! not part of b3.1

Question 1

type I pneumocyte

Answer 1

squamous and thin
95% of alveolar surface
involved in gas exchange
very few organelles
act as tight junctions

Question 2

type II pneumocyte

Answer 2

cuboidal
5% of alveolar surface
secrete surfactant into alveolar space
more organelles (lamellar bodies)

Question 3

type II pneumocyte organelles

Answer 3

lamellar bodies are secretory vesicles (these secrete surfactant made of lipids + phospholipids + prevent alveoli from collapsing)

Question 4

more plentiful pneumocyte

Answer 4

type II

Question 5

Competitive and non-competitive inhibition

Answer 5

competitive mimics substrate and binds to enzyme at main cite, non-competitive binds to allosteric cite and alters conformation

Question 6

non-competitive inhibition examples

Answer 6

hexokinase and glucose 6-phosphate, statin drugs

Question 7

exercise on co2 production

Answer 7

during exercise need more atp (because skeletal muscles contract and atp fuels them) co2 is released as a byproduct

Question 8

co2 production and blood ph

Answer 8

creates carbonic acid h2co3 by reacting with water in plasma, dissociates to H+ ions making it more acidic

Question 9

ventilation feedback loop

Answer 9

pH sensed by chemoreceptors in aorta and carotid artery, neurons fire to action potential, signals medulla oblongata which sends signals to lungs and heart
greater blood flow, gas exchange increase

Question 10

Lung and heart response to medulla oblongata

Answer 10

Lungs: Diaphragm and intercostal contract more rapidly to increase rate of ventilation and tidal volume, co2 decrease, pH increase
Heart: heartbeat rate increase, pump force increase

Question 11

Hyperventilation occurs in response to exercise

Answer 11

more co2 produced = need more o2 = need more ventilation = processes increase in rate and force (forced breathing increases)