respiratory revision

Question 1

describe what happens during inspiration in exercise

Answer 1

diaphragm contracts and flattens, external intercostal pulls ribs up, sternocleidomastoid pulls sternum up, increases volume of thoracic cavity, decreases pressure in lungs, more air into lungs.

Question 2

describe what happens during expiration in exercise

Answer 2

diaphragm relaxes and dome shape, internal intercostals pull ribs down, rectus abdominis and transverse abdominis contract, pushes diaphragm up, reduces volume of thoracic cavity, creates larger pressure gradient, more air out of lungs.

Question 3

what is partial pressure

Answer 3

pressure exerted by an individual gas in amongst a number of gases

Question 4

describe external diffusion of O2

Answer 4

o2 been depleted from blood supply, partial pressure of o2 breathed into lungs is high, pressure gradient between alveoli to blood, o2 diffuses into capiliries, o2 binds with haemoglobin to be transported around the body.

Question 5

describe internal diffusion of O2

Answer 5

oxygen moves from blood to muscles, high partial pressure as breathed in, pressure gradient from blood to muscles, high concentration of O2 in the blood diffuses into muscle cells which binds with myoglobin.

Question 6

describe external diffusion of CO2

Answer 6

co2 waste product of respiration so high partial pressure in blood, the pressure of this going into lungs is lower though, pressure gradient from blood to alveoli, co2 molecules diffuse into capiliries, breathed out of lungs.

Question 7

describe internal diffusion of CO2

Answer 7

Co2 moves from muscle to blood, low partial pressure, gradient between muscle to blood, high concentration of co2 in muscle cells diffuses into blood which gets transported back into lungs

Question 8

tidal volume

Answer 8

volume that enters and leaves with each breath.

Question 9

residual volume

Answer 9

volume remaining after maximum expiration

Question 10

vital capacity

Answer 10

volume that can be exhaled after maximum inspiration

Question 11

what is a spirometer and how does it work

Answer 11

device that measures amount of air you’re able to breath in and out and the time it takes you to exhale completely after a deep breath. Works by you breathing into a tube attached to machine.

Question 12

describe the respiratory centre

Answer 12

has the medulla oblongata. Involves the inspiratory centre (works during rest and exercise) and the expiratory centre (only works during exercise). they receive info about chemical balance and processses that info to send signals to muscles to change rate and depth of breathing.

Question 13

describe where the chemoreceptors are located and what they do

Answer 13

located in central (medulla..) or peripheral (aortic body). they detect changes in O2, co2 or ph levels.