Success Criteria
 I can…

describe the role of the cell membrane in cells

recognise and label fats and proteins in the membrane.


Describe the cell membrane as being selectively
permeable and having a non rigid structure
Describe the meaning of the term ‘selectively
permeable’.
Recap…
 You already know that all cells have a cell membrane
Cell
membrane
Animal cell
Cell Membrane is to the inside of the
cell wall
Plant Cell
A closer look…
Cell Membrane
Parts of cell membrane
 The cell membrane consists of a few components…
 Proteins (Some of which have pores/
Protein
channels)
 A double layer of Phospholipids (fats)
 We can describe this as a phospholipid bilayer
Phospholipids (fats)bilayer
Fluid mosaic model…
 The cell membrane can be described as being an
example of a ‘fluid mosaic model’.


Mosaic-This means there are many different components
pieced together (phospholipids(fats) and proteins)
Fluid- This means it is a non rigid (moving) structure
 http://www.stolaf.edu/people/giannini/flashanima
t/lipids/membrane%20fluidity.swf
Recap-
Function
 The function of the cell membrane is…

to control entry and exit of substances to the cell
Selectively Permeable….
The cell membrane can be thought of as a guard or bouncer.
 It doesn’t let just any molecules into or out of the cell…. It
is selective.
 Only small molecules such as oxygen, water, carbon dioxide
and glucose are able to pass through the membrane easily.
We refer to this as the cell membrane being selectively
permeable (it only lets some molecules pass through).
 http://www.youtube.com/watch?v=Rl5EmUQdkuI&feature
=fvwrel
Success Criteria
 I can…

describe the role of the cell membrane in cells

recognise and label fats and proteins in the membrane.


Describe the cell membrane as being selectively
permeable and having a non rigid structure
Describe the meaning of the term ‘selectively
permeable’.