Biology Forums - Study Force

23. (a) Differentiate clearly between Minute respiratory volume and alveolar ventilation rate. (b) Which provides a more accurate measure of ventilatory efficiency, and why? (4 points) Answer:

25. (a) Define hyperventilation. (b). If you hyperventilate, do you retain or expel more carbon dioxide? (c) What effect does hyperventilation have on blood ph? (4 points) Answer:

26. Describe age-related changes in respiratory function? (4 points) Answer:

VE (Minute Ventilation) = VT (Tidal Volume) x F (Frequency)

VA (Alveolar Ventilation) = (VT-VD) x F

VD = Dead Space Volume (1 ml/lb lean body weight)

Alveolar Minute Ventilation accounts for the volume moved into and out of the lungs that take place in gas exchange, whereas Minute Ventilation includes all volume of air that moves into and out of the lungs, those that do and dont involve themselves in gas exchange.

another respiratory student. ok, let me clarify using theorectical text book stuff. this is for a healthy 20 year old at rest.

1. respiratory minute volume is Vt (tidal volume) x RR or f (resp. rate).
ex: 500cc x 12 = 6000cc breathed in a minute. thats your respiratory volume

2. alveolar volume is (vt -dead space) x rr . the average dead space is about 150cc give or take a few.
ex: 500cc - 150 = 350 x 12 = 4200cc alveolar volume (ventilation)

everything is else is smoke and mirrors.

for # 1, there is no big mystery here, it's the dead space ventilation. You can calculate that easily enough yourself. If you're asking this question than you already have a idea what we're talking about and could have looked it up in your text.

Minute ventilation - the volume of air that flows into or out of the lung in one minute. Alveolar ventilation - the volume of air that flows into or out of the alveolar space in one minute