Chapter 7.2

1
Chapter 7.2 7.4Cell Transport
2
Cell Membrane Review

• Essential for homeostasis
• Selectively permeable

3
Membrane Structure

• Flexible (fluid) due to cholesterol
• Made up of many parts (mosaic)
• Lipid bilayer

4
Phospholipid

• Main part of cell membrane
• Hydrophilic head
• Hydrophobic tails (lipid)

5
Two layers of phospholipids
6
(No Transcript)
7
(No Transcript)
8
Membrane Proteins

• Have specific functions
• Identify cell
• Receive info
• Transport materials

9
Membrane Proteins (cont.)

• Stroke blood clot blocks O2 flow to brain
• Affects Ca pump
• Excess Ca causes
• cell death

10
Membrane Proteins (cont.)

• Drugs Brain
• Over stimulate receptors

http//learn.genetics.utah.edu/content/addiction/d
rugs/mouse.html
11
An Animal Cells Environment

• Water, oxygen glucose enter the cell
• Water, wastes carbon dioxide exit the cell

12
Chapter 7.4Types of Transport
Insane in the Membrane
13
Passive Transport

• Movement of molecules across cell membrane
  without energy
• Ex Diffusion, Osmosis Facilitated Diffusion

14
1. Diffusion

• Movement of solute molecules
• Higher to lower concentration
• Solutes oxygen, salt

15
(No Transcript)
16
Diffusion
17
Diffusion Animation

• http//highered.mcgraw-hill.com/sites/0072495855/s
  tudent_view0/chapter2/animation__how_diffusion_wor
  ks.html

18
2. Osmosis

• Movement of water (solvent) molecules
• Higher to lower concentration
• Solvents dissolve solutes

19
Osmosis
H2O
20
Osmosis Animation

• http//highered.mcgraw-hill.com/sites/0072495855/s
  tudent_view0/chapter2/animation__how_osmosis_works
  .html

21
Homeostasis Connection

• Solute solvent want to be in equal
  concentrations

22
Osmosis
Solvent
Solute
23
3. Facilitated Diffusion

• Diffusion using proteins in cell membrane
• Used for molecules that are large (Ex. Glucose)

24
3. Facilitated Diffusion (cont.)

• Molecules with a specific shape can pass through

25
Active Transport

• Process that moves molecules from lower
  concentration to higher concentration
• Helps store molecules
• Requires energy

26
Sodium-Potassium Pump

• Example of active transport
• Helps nerves and muscles function properly

27
Endocytosis Exocytosis

• Used when things are too large to pass through
  the cell membrane by any other method

28
Endocytosis

• Process where cells ingest fluids, large
  particles, macromolecules other cells

29
Examples of Endocytosis

• Amoeba unicellular organisms feeds this way
• White blood cells use endocytosis to engulf
  destroy bacteria viruses

30
Endocytosis
31
Exocytosis

• Process where cells release substances
• Organelles fuse with cell membrane release
  contents