Pages in this set

Page 1

Preview of page 1
The Cell Surface Membrane
All membranes around and within cells have the same basic structure and are known as
plasma membranes.
The cell-surface membrane is the plasma membrane that surrounds cells and forms a
boundary between the cell cytoplasm and the environment.

It allows different conditions to be established inside…

Page 2

Preview of page 2
Lipids
Phospholipids
Phospholipids form a bilayer sheet.

They make up 75% of the lipid.

They are an important component of the cell surface membrane for the following reasons:

- One layer of phospholipids has its hydrophobic heads pointing inwards -
interacting with the water in the cell cytoplasm
- The…

Page 3

Preview of page 3
Glycolipids
Glycolipids make up 5% of membrane lipids.

They occur on the external surface of the cell surface membrane and the carbohydrate
portion of the glycolipid extends into the intercellular space and is called a glycocalyx. These
are important cell to cell recognition.



Cholesterol
A steroid which makes up 20%…

Page 4

Preview of page 4
Proteins
The proteins of the cell surface membrane are arranged more randomly than the regular
pattern of phospholipids.

They are embedded in the phospholipid bilayer in two main ways:

Extrinsic proteins
Occur either on the surface of the bilayer or only partly embedded in it.

They never extend completely across…

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all resources »