gas exchange systems at the alveoli and muscles

Question 1

what is gaseous exchange?

Answer 1

movement of oxygen from air into the blood and carbon dioxide from blood into the air

Question 2

what is partial pressure

Answer 2

the pressure exerted by an individual gas when it exists within a mixture of gases

Question 3

what is diffusion

Answer 3

the movement of gas molecules from an area of high to low concentration or partial pressure

Question 4

what are the adaptations of the alveoli to make them suitable for gas exchange

Answer 4

one cell thick so short diffusion pathway, excellent blood supply as they have an extensive capillary network, higher surface area as there r millions of alveoli so greater uptake of oxygen

Question 5

is concentration and therefore partial pressure of oxygen higher in the blood or in the alveoli

Answer 5

in the alveoli(100mmHg), the blood is 40mmHg meaning oxygen diffused from the alveoli into the blood

Question 6

what is a concentration gradient

Answer 6

the difference in partial pressure, the bigger the gradient the faster diffusion will be

Question 7

does carbon dioxide move from the blood into the alveoli?

Answer 7

yes, partial pressure of co2 in the blood is 45mmHg whereas in the alveoli it’s 40mmHg

Question 8

is the partial pressure of oxygen lower in muscle tissues or in the blood

Answer 8

in the muscle tissues/capillary membranes partial pressure of oxygen is 40mmHg whereas its 100mmHg in the blood, so oxygen diffuses from the blood into the muscle tissues

Question 9

is the partial pressure of carbon dioxide higher in the blood or muscle tissures

Answer 9

in the muscle tissues which is 45mmHg, the alveoli is 40mmHg so it diffuses from the muscle tissues into the blood where it will be transported to the lungs