Monosaccharide and disaccharide isomerization over Lewis acid ...
Cell Membranes Separating Dead from Alive. Identify the radical below. 1.Amine 2.Hydroxyl 3.Carboxyl...
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Transcript of Cell Membranes Separating Dead from Alive. Identify the radical below. 1.Amine 2.Hydroxyl 3.Carboxyl...
Identify the radical below.
19%
0%
57%
24%
1. Amine
2. Hydroxyl
3. Carboxyl
4. Monosaccharide
Identify the molecule shown.
62%
33%
0%0%5%
1. Butene
2. Propene
3. Propane
4. Butane
5. None of the above are a good response.
What is the function of the molecule shown below?
40%
5%5%
50%
1. Energy storage
2. Component of cell membrane
3. Fuel source
4. Regulatory
I. Functions
Living part of the cell-legitimate cell organelle
Separates living from the nonliving world
Semipermeable-regulates what enters and exits the cell
Partitions the cell into different regions where different functions take place
Participates in chemical reactions
Transmits signals between outside of cell and the cytoplasm[
II. Cell membrane characteristics
• A. Semipermeable
• B. Elastic
• C. Wettable
• D. Very thin-around 10 um
II. Early model
• A. Davison Danielli Model
1. mainly lipid
2. aqueous channels
3. surface protein
4. weaknesses
III. Fluid mosaic model
• A. Main ingredients
• Phospholipids• Proteins both
intrinsic and extrinsic
• Cholesterol• Glycocalyx
What do you think the function of this membrane protein might be?
1. Transport
2. Cell to cell adhesion
3. Cell to cell recognition
4. Energy production
Electron micrograph of cell membrane
• http://www.med.uiuc.edu/histo/large/atlas/image/temgi3/75000a1.htm
C. Chemical properties of membrane
• 1. Lateral fluidity• 2. Two dimensional
fluidity-rapid movement of lipids and proteins
• 3. Flexible• 4. Self sealing• 5. Can fuse
IV. Function of Cell Membrane-Passive Transport
A. Diffusion
1. definition
2. example
3. across cell membrane
IV. Function of Cell Membrane-Passive Transport• B. Facilitated
Diffusion1. mediated by intrinsic protein2. diffusion gradient-no ATP3. glucose entrance into cell4. boy scout analogy
C. Osmosis
• 1. Definition• 2. U-tube• 3. Explanation• 4. Common examples• 5. Terms of tonicity• 6. Turgor pressure
In which direction will water move?
1. A => B and B rises
2. B => A and A rises
3. A B and the sides stay at the same level
4. No idea
Figure 5-13
Page 106
Plasmamembrane
Vacuole
Vacuolarmembrane(tonoplast)
CytoplasmPlasmamembrane
Vacuole
Nucleus(a) (b) (c)
D. Membrane Pumps
1. Materials are moved against concentration gradient
2. An integral protein molecule is involved
3. ATP is necessary
4. Sometimes membrane potentials are produced
5. Na ion-K ion pump is an example
Figure 5-15b
Page 108
ATP
ADP
1. Three sodium ions bindto the transport protein
2. A phosphate group istransferred from ATP tothe transport protein
3. The transport protein under-goes a conformationalchange, releasing threesodium ions outside the cell.
6. The transport proteinreturns to its original shape:Two potassium ions arereleased inside the cell
5. The phosphate is released
4. Two potassium ions bindto the transport protein
(b)