Lecture 18 Mar 8 lecture

Lecture 18 Mar 8 lecture - 17:38 Movement of Gases Gas...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
17:38 Movement of Gases Gas exchange = uptake of O 2  and discharge of CO 2 Partial pressure is the driving force for gas exchange At 760 mmHg (sea level) P O2  of oxygen (21% of composition of air) equals 760 x 0.21 =  160 mmHg Oxygen content of water Amount of gas in water is proportional to partial pressure of gas above and it solubility  (salinity and temperature) Even though O O2  is 160 mmHg there is much less O 2  in water due to its low solubility (4  to 8 mL of O 2  per L of water, 0.4 to 0.8%) Life has evolved methods to exchange gases in water Water serves as a source of oxygen Gas exchange in water is very demanding Some general themes Respiratory surfaces are moist Plasma membrane is in contact with aqueous solution Gas exchange is fast when the area for diffusion is large and path is short Endotherms have larger respiratory surface than ectotherms
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 03/14/2012 for the course BISC 13141 taught by Professor Williammcclure during the Spring '10 term at USC.

Page1 / 6

Lecture 18 Mar 8 lecture - 17:38 Movement of Gases Gas...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online