11.2.05

# 11.2.05 - November 2 2005 Announcements 1 Dinind Discussion...

This preview shows pages 1–3. Sign up to view the full content.

November 2, 2005 Announcements: 1) Dinind Discussion – Women in Science 2) Friday In-Class Discussion – Read NY Times Article Lecture 29: Circulation and gas  exchange The problems of being big When you are small, water can diffuse in and out, as can food This doesn’t work in really big elephants, or big organisms Why? Fick’s Law o Q= -DA ∆C/∆x, C is concentration, X is distance, D is diffuse scoefficient, A is area, q is diffusion More Problems: The scale and time o Diameter =x, time to diffuse = T Distance concentration This shows that the longer the distance you need to go to diffuse across membrane, the time (rate aka slope) at which you diffuse decreases drastically.

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

View Full Document
o Diameter = 2x, time to diffuse = 4T Surface Area : Volume o Diameter = x, SA = πx2, Vol = (π/6) x3 o Ratio is 1/6, and decreases drastically as diameter increases Evolutionary Adaptations: Surface area (i.e. gills, lungs microvilli, leaves, etc) A Solution
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 02/11/2008 for the course BIO G 101 taught by Professor Gilbert,c. during the Fall '07 term at Cornell.

### Page1 / 3

11.2.05 - November 2 2005 Announcements 1 Dinind Discussion...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online