{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Lecture11

# Lecture11 - Lecture 13 Circulation and Gas Exchange Chapter...

This preview shows pages 1–10. Sign up to view the full content.

Lecture 13: Circulation and Gas Exchange Chapter 42

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

View Full Document
organic energy (carbohydrate) ATP (usable cellular energy) mitochondria C 6 H 12 O 6 ATP
organic energy (carbohydrate) ATP (usable cellular energy) C 6 H 12 O 6 + O 2 CO 2 + H 2 O + ATP oxygen carbon dioxide mitochondria O 2 CO 2

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

View Full Document
J = D x A x (C1 - C2) / L Fick’s Law - equation describing factors that affect diffusion rates of molecules (such as oxygen) across a membrane J = diffusion rate across absorptive surface D = constant A = surface area of absorptive surface C1 = concentration of molecule on side A of surface C2 = concentration of molecule on side B of All gas exchange between environment and cells occurs via diffusion!
J = D x A x (C1 - C2) / L J = diffusion rate across absorptive surface D = constant A = surface area of absorptive surface C1 = concentration of molecule on side A of surface C2 = concentration of molecule on side B of surface L = distance traveled of C1 molecule to C2 low oxygen HIGH oxygen J = D x A x (C1 - C2) / L J = 1 x 100 x (100 - 10) / 1 J = 9000 mol/m 2 /sec how about if we increase our surface area to 500?

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

View Full Document
HIGH oxygen J = D x A x (C1 - C2) / L J = 1 x 500 x (100 - 10) / 1 J = 45,000 mol/m 2 /sec J = D x A x (C1 - C2) / L J = diffusion rate across absorptive surface D = constant A = surface area of absorptive surface C1 = concentration of molecule on side A of surface C2 = concentration of molecule on side B of surface L = distance traveled of C1 molecule to C2 large increases in A (or decreases in L) lead to much higher diffusion rates
low oxygen HIGH oxygen Diffusion time of molecules through media is inversely proportional to the square of the distance traveled d = diffused distance D = constant t = time d 2 = 2Dt if d = 10, then t = 50 100 = 2 (1) 50

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

View Full Document
low oxygen HIGH oxygen simple diffusion is sufficient for cells close to the surface, but as we increase our distance traveled the time to achieve diffusion increases greatly Diffusion time of molecules through media is inversely proportional to the square of the distance traveled d = diffused distance D = constant t = time d 2 = 2Dt if d = 100, then t = 5000 10,000 = 2 (1) 5000
Diffusion time of molecules through media is inversely proportional to the square of the distance traveled d t 0.1mm 1s 1mm 100s 1cm 3 hours

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

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 51

Lecture11 - Lecture 13 Circulation and Gas Exchange Chapter...

This preview shows document pages 1 - 10. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online