Download Plasma Membrane

Survey
yes no Was this document useful for you?
   Thank you for your participation!

* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project

Document related concepts
no text concepts found
Transcript
Plasma Membrane
Plasma Membrane
Structure
 Phospholipid bi-layer
Structure
 Phosphate Head – Hydrophilic
 Lipid Tail – Hydrophobic
 Glycoprotein/Glycolipids – Cell markers
 Carrier Protein – Passive and Active
Structure
Carbohydrate cell
markers
Proteins
Floating Mosaic
Phospholipid molecules
Function of the Plasma
Membrane
 - selectively permeable membrane
 - allows for communication between cells
 - provides the cell with a specific “marker”
Plasma Membrane
 Construction of the Cell Membrane Learning Ac - Flash Player Installation
Carrier Protein
 Passive Channel – Leakage channel
 Active Channel – Open and close to let
larger molecules through

- Uses Cellular energy
(ATP)
 Channel Protein
Particle Theory
 1. All matter is made of particles
 2. The particles are in constant motion
(Kinetic motion of particles)
 3. The closer the particles are together,
the greater the attractiveness between
them.
Particle Theory
 Solids – definite shape and volume
 Liquids – definite volume but indefinite
shape
 Gases – indefinite shape and volume
 Matter
Cellular Transport
 Passive Transport – use no cellular
energy
 A) Diffusion
 B) Osmosis
 C) Facilitated Diffusion
A. Diffusion
 - Movement of particles from an area of
High concentration to an area of Low
concentration
 - Particles will move until they are evenly
distributed in an Equilibrium
 - Particles continue random movement,
but it has no affect on the equilibrium
 Diffusion
B. Osmosis
 - special diffusion where water passes
through a selectively permeable
membrane from an area of High
concentration to an area of Low
concentration
 Osmosis
 Osmosis II
C. Facilitated Diffusion
 - special diffusion that is made faster by
using Passive Channels (leakage
channels)
 - can result in a conformational change in
the shape of the protein.
 Facilitative Diffusion
 Facilitated Diffusion II
 Facilitated Diffusion III
Try these:
 1. The plasma membrane consists of ___ layers.
 2. The molecules that make up the plasma membrane
are called ______
 3. The phosphate heads like water and are called
______.
 4. The lipid tails don’t like water and are called ______.
 5. Special protein molecules called _____ are found
throughout the plasma membrane.
 6. Cell markers called _______ are attached to the top
of these protein molecules.
 7. The Particle Theory states that all matter is made up
of tiny particles and that they are in _________.
 8. Cells need to move materials in and out to maintain
a state of balance between what is inside and outside.
This balance is called _______
 9. Cells move materials in and out in 2 ways.
___________ and ___________
 10. ________transport doesn’t require the cell to
expend any energy.
 11. ________ transport requires the cell to use some of
it’s own energy stored in _____
 12. There are 3 types of Passive Transport ________,
_________ and __________.
 13. Movement of any particles from H to L is called
________.
 14. Movement of water molecules from H to L is called
________.
 15. Diffusion of particles that are helped by carrier
protein is called __________.
Review of Passive
Transport
 Passive Transport
Environments that Cells
might find themselves in:
 A) Hypotonic Solutions – greater concentration
of water OUTSIDE the cell
 B) Hypertonic Solutions – greater
concentration of water INSIDE the cell
 C) Isotonic Solutions – even concentrations of
water inside and outside the cell
How will cells react in
each??
 Animal cells
 Hypotonic Solution
 - water moves into the cell (osmosis), the
cell swells, and may burst (Cytolysis)
 Hypotonic Solution
How will cells react in
each?
 Animal cells
 Hypertonic – water moves from inside
out and the cell shrivels and dehydrates
 Hypertonic
How will cells react in
each?
 Animal cells
 Isotonic – water moves in and out of the
cell at the same rate (Random movement)
 Isotonic
Another look:

Solutions
What about plant cells?
 Hypotonic – water moves in and Turgor
Pressure in the cell increases.
What about plant cells?
 Hypertonic – water moves out of the cell
and turgor pressure drops

- the plasma membrane pulls
away from the cell wall and the cell wilts.
 Plasmolysis
What about plant cells?
 Isotonic – water moves in and out at the
same rate.
Another look:
Cellular Traffic
 Active Transport (uses ATP)
 A) Endocytosis
 B) Exocytosis
 C) Movement against the “concentration
gradient”.
Cellular Traffic
 A) Endocytosis – movement of large particles
into a cell packaged in vesicles . The cell uses
energy stored in ATP
 i) Phagocytosis  - cell engulfs a large food particle by wrapping
it’s cytoplasmic arms around the particle
 Phagocytosis
Cellular Traffic
 i) Pinocytosis – cell engulfs a smaller
particle or water droplet into the cell by
indenting the plasma membrane. The cell
uses energy stored in ATP
 Pinocytosis
 Pinocytosis 2
Cellular Traffic
 B) Exocytosis – excreting materials from
a cell packaged in vesicles. The cell uses
energy stored in ATP.
 Exocytosis
 Exocytosis 2
Cellular Traffic
 C) Movement against the Concentration
Gradient (L to H)
 Particles are drawn against the concentration
gradient using active channels that open and
close using cellular energy
 L to H
 L-H
Cellular Transport Review
 Thirst Reflex
 Passive Transport
 Environments
 Drag and Drop Cell membrane
Homeostasis
 All these examples of cellular traffic are
designed to help the cell maintain a state
of balance between the inside and the
outside of the cell.