Ctools012111lecture07

Ctools012111lecture07 - Biology 172 Lecture 7: Friday,...

Info iconThis preview shows pages 1–11. Sign up to view the full content.

View Full Document Right Arrow Icon
Lecture 7: Friday, January 21, 2011 Biology 172 Today’s Outline Announcements Exam I is Mon., Jan. 31, 6-8 pm. Review in class Mon., Jan. 1 • UM Biological Station Classes & Research Experience (CTools) Membrane Transport Passive Transport Simple diffusion Facilitated diffusion Active Transport Biological Macromolecules Proteins Carbohydrates Nucleic Acids Lipids
Background image of page 1

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

View Full DocumentRight Arrow Icon
Membranes are a “mosaic” of many macromolecules
Background image of page 2
Outside cell Peripheral membrane protein Integral membrane protein Peripheral membrane protein Inside cell Membrane Proteins Many proteins are partially, or entirely, located within a membrane. These are integral membrane proteins . How might these proteins differ from soluble proteins? Figure 6.19
Background image of page 3

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

View Full DocumentRight Arrow Icon
(a) Proteins can be amphipathic. (b) Amphipathic proteins can integrate into lipid bilayers. The polar and charged amino acids are hydrophilic The nonpolar amino acids are hydrophobic Outside cell Inside cell Figure 6.16
Background image of page 4
Hydrophilic channel Sequential steps in metabolic pathway Relay chemical messages Various cell junctions Glycoprotein identification tags Cell shape and stabilize proteins Functions of membrane proteins
Background image of page 5

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

View Full DocumentRight Arrow Icon
BIOLOGICAL MEMBRANES Fluid Mosaic Model Membrane Structure Transport Across Membranes Passive Transport Simple Diffusion Facilitated Diffusion Active Transport
Background image of page 6
Membrane permeability: Molecules vary in their ability to cross membranes based on their size, polarity, and charge Figure 6.7 High permeability O 2 , CO 2 , N 2 H 2 O, glycerol 100 Permeability scale (cm/sec) Glucose, sucrose Cl , K , Na 10 2 10 4 10 6 10 8 10 10 10 12 Low permeability Phospholipid bilayer Ions Large, uncharged polar molecules Small, uncharged polar molecules Small, nonpolar molecules
Background image of page 7

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

View Full DocumentRight Arrow Icon
Transport Across Membranes membranes are selectively permeable barriers Simple Diffusion movement of molecules across a membrane down a concentration gradient no energy required not saturable
Background image of page 8
Simple Diffusion Cell membranes are permeable to small hydrophobic (nonpolar) molecules ( e.g., hydrocarbons, CO2, O2) Molecules move randomly, but net movement is down concentration gradient The cell provides no energy Net diffusion Net diffusion of each solute down its own concentration gradient Equilibrium
Background image of page 9

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

View Full DocumentRight Arrow Icon
membranes are selectively permeable barriers Facilitated Diffusion movement of molecules
Background image of page 10
Image of page 11
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 02/13/2012 for the course BIO 172 taught by Professor Clark during the Winter '08 term at University of Michigan.

Page1 / 46

Ctools012111lecture07 - Biology 172 Lecture 7: Friday,...

This preview shows document pages 1 - 11. Sign up to view the full document.

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