Fluid Mosaic Model of the Cell Membrane

1
Fluid Mosaic Modelof the Cell Membrane

• Components
• -Are In Fluid, consistent movement
• Phospholipid bilayer
• Embedded proteins
• Exterior proteins and lipids
• -ID markers Glycolipids, Glycoproteins
• -receptors

2
(No Transcript)
3
Phospolipids

• Consist of
• Glycerol
• Fatty acids (2)
• alcohol with P group (highly polar)
• They are partly Hydrophilic and partly
  Hydrophobic
• Heads polar, attracted to H2O (phosphate
  group)
• Tails nonpolar, repelled by H2O (fatty
  acids)

4
Phospolipid Bilayer is

• Permeable to
• Small polar molecules (eg. H2O but limited )
• Non-polar molecules (eg. Lipids, CO2)
• Non Permeable to
• Ions
• Lg. Polar molecules (eg. Glucose)
• But these are necessary so how do
  they get in?

5
Methods of in/out movement

• Diffusion
• -substances move from areas of high to
  low concentration
• Osmosis diffusion of H2O
• -Isotonic
• -Hypotonic
• -Hypertonic solutions
• Cells in Hypotonic water how do they survive it?
• Adaptations cell wall
• - pump (contractile
  vacuole)
• Turgor pressure in plants

6
(No Transcript)
7

• 2. Bulk transport energy intensive
• - Endocytosis
• Phagocytosis (solid)
• Pinocytosis (liquid)
• -Exocytosis
• 3. Facilitated Diffusion no energy, passive
• -Carrier proteins
• -Ions, sugars, amino acids use this method
• -With the conc. gradient
• -Binds with protein, then released

8
(No Transcript)
9

• Active transport energy intensive
• -Against conc. gradient
• -eg. Na/K pump
• -Storage (eg. Glucose in liver cells)
• 5. Ion channels passive
• -Protein tunnels (H2O filled)
• -Ions diffuse through
• 6. Aquaporins water channels

10
(No Transcript)
11
(No Transcript)