Question

Completely and utterly confuzzled on this... any help appreciated as always. =D
**A&P Course Q**Why is the composition of alveolar air different from that of the atmosphere ? What 4 factors affect the efficiency of alveolar gas exchange?

Answer 1

Q#1 The atmosphere consists up to 70 or 80% out of Nitrogen. The air in the Alveolar doesn't, we don't inhale the nitrogen into our lungs it is filtered out. Along Trachea there are small Cilium which are small flagellas which continously move particles away from the lungs which acts as a filter. Mucus and the hair in our nose catches diffrent pathogens along with dust particles and any other unwanted particles.
Summary: The upper respiratory tract cleanses, humidifies and heats up the air along it's decend down to the Alveols.

Answer 2

You're awesome, thanks a bunch! XD Do you happen to know what the factors are? jw, been having trouble finding them. -.-

Answer 3

Q#2
These are the only ones that i can think of :
The alveoli are covered in a series of blood vessels and capillaries which mean that the gasses can diffuse directly into the bloodstream.
Red Bloodcells are also slowed as they flow through the capillaries, this allows more time for the gases to diffuse across the alveolar epithelium and the endothelium of the capillaries and the alveoles.

Availability of oxygen & RBC (Red bloodcell count)

Answer 4

Totally awesome, thanks for the help, super appreciated. Ive been having crazy mindblocks lately >.< thanks!!

Answer 5

Glad i could be of help.

Answer 6

You might also consider the role of surfactant in the alveoli - this is a naturally occurring fluid that lowers surface tension in the alveoli. I think this means that the lungs can expand more easily, which can only be a good thing for oxygen diffusion. Otherwise the partial pressure of oxygen is important - in simpler terms if you're up in the atmosphere where the air is thin the diffusion will be less than at or below sea level. exuras was on to this when mentioning availability of oxygen. I guess pulmonary edema might change things too - this is excess fluid in the lung which slows the diffusion. I hope this helps