NATS 1675 Lecture Notes - Lecture 20: Basement Membrane, Circulatory System, Atmospheric Pressure

• School: York University
• Department: Natural Science
• Course: NATS 1675
• Professor: Robert Crippen

Document Summary

Some particles that enter villi do get deposited into . Smokers/ coal miners at risk; particles if not removed then get deposited into tissues of lungs (asthma, bronchitis, emphysema, cancer) Has a concentration gradient; high to low concentration. Gas transfers by simple diffusion: must pass through the cells making up the alveolus, basement membrane, walls of the capillaries. Basement membrane is layer of nonliving material and serves to anchor the cells making up the alveoli with smaller tissues. Air is a mixture of gases primarily nitrogen (n2), oxygen (o2) and carbon dioxide (co2). There are a number of other minor gases of which we are not concerned. Gas exerts pressure, and the total pressure of a gas is = to the sum of the pressures of the individual component gasses. Atmospheric pressure = 760 mm hg at sea level. O(cid:1006) (cid:1006)(cid:1005)% of the at(cid:373). , therefore (cid:1004). (cid:1006)(cid:1005) (cid:454) (cid:1011)(cid:1010)(cid:1004)(cid:373)(cid:373) hg = (cid:1005)(cid:1010)(cid:1004) (cid:373)(cid:373) hg.