Download S10 Cell membrane properties

Dynamic Cells
Chapter 8 p. 288 - 317
Membrane
Properties
Transport Across Cell Membranes
Cell Size and Functions
Membrane Properties
pg. 290 - 296
Membrane
Structure
Membrane Function
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http://www.teachersdomain.org/asset/oer
08_vid_bassler/
Bacterial membrane and communication
Cell membranes are
phospholipid bilayers
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https://www.youtube.com/watch?v=yAXn
YcUjn5k
TedEd Insights into cell membranes via dish detergent
Cell membranes are
phospholipid bilayers
What are phospholipids?
Phospholipids self assemble into
different structures because their
hydrophobic and hydrophilic ends
repel each other
What’s a Phospholipid Bilayer?
2 layers of phospholipids
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Each layer has:
◦ a hydrophilic phosphate end (hydro = water,
philic = loving)
◦ and a hydrophobic lipid tail (phobic = fears,
repels)
Cell membranes are like mosaics
Lots of phospholipid tiles with protein,
carbohydrate chain and cholesterol tiles
thrown in!
Why the
different tiles?
Membranes are
responsible for an
incredible number of
things!
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carbohydrate chains are for cell to cell
communication.
Proteins are crucial for
the transport of
substances in and out of
the cell
Membrane Proteins can be peripheral
(on surface) or integral (spans the
membrane)
Cholesterol maintains proper
membrane flexibility, and also is
crucial for cell signaling and nerve
conduction.
Cholesterol is not just a bad guy!
Fluid Mosaic Model
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Cell membranes are constantly MOVING
and CHANGING.
Fluid Mosaic Model
Gives cell flexibility, movement
RBC membrane
Changes the positions of the proteins, lipids
and carbohydrates embedded in the
membrane, changing the “mosaic” to meet
changing needs
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https://www.youtube.com/watch?v=Qqsf_
UJcfBc
3 Functions of the Cell Membrane
1. Barrier – keeps “baddies out, cell organelles in
Bacteria
pollution resistant bacteria
3 Functions of the Cell Membrane
2.
Organization – membranes surround
and package materials in vesicles,
lysosomes
endoplasmic reticulum
2. Organization – membranes
organize complex reactions like
photosynthesis and cellular respiration
3. Selective Filter – SEMI-PERMEABLE –
only allows certain substances in or out
 Regulated by particle size and by selective
transport by membrane proteins
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https://www.youtube.com/watch?v=GW0l
qf4Fqpg&feature=related
Cell membrane receiving info from hormone
Clips
http://www.youtube.com/watch?v=Rl5EmUQdkuI&featu
re=fvwrel
fluid mosaic model
 http://www.youtube.com/watch?v=GW0lqf4Fqpg&featur
e=related
how a hormone communicates to the cell through the
membrane
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http://www.teachersdomain.org/asset/oer08_vid_bassle
r/
Membrane communication in bacteria – antibiotic
potential
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