Download cell membrane

The Cell Membrane
 Cell membranes are composed of two phospholipid
layers.
The Cell Membrane
 Cell membranes are composed of two phospholipid
layers.

The cell membrane has two major functions.
The Cell Membrane
 Cell membranes are composed of two phospholipid
layers.

The cell membrane has two major functions.

forms a boundary between inside and outside of the cell
cell membrane
inside cell
outside cell
The Cell Membrane
 Cell membranes are composed of two phospholipid
layers.

The cell membrane has two major functions.
forms a boundary between inside and outside of the cell
controls passage of materials

cell membrane
inside cell
outside cell
The Cell Membrane
 Cell membranes are composed of two phospholipid
layers.
The Cell Membrane
 Cell membranes are composed of two phospholipid
layers.

The cell membrane is made of a phospholipid bilayer.
cell membrane
The Cell Membrane
 Cell membranes are composed of two phospholipid
layers.


The cell membrane is made of a phospholipid bilayer.
There are other molecules embedded in the membrane.
cell membrane
carbohydrate
chain
cholesterol
protein
protein channel
protein
The Cell Membrane
 Cell membranes are composed of two phospholipid
layers.



The cell membrane is made of a phospholipid bilayer.
There are other molecules embedded in the membrane.
The fluid mosaic model describes the membrane.
cell membrane
protein
carbohydrate
chain
cholesterol
protein channel
protein
The Cell Membrane
 Cell membranes are composed of two phospholipid
layers.
The Cell Membrane
 Cell membranes are composed of two phospholipid
layers.

The cell membrane is selectively permeable.
Some molecules can cross the
membrane while others cannot.
The Cell Membrane
 Cell membranes are composed of two phospholipid
layers.

The cell membrane is selectively permeable.
Some molecules can cross the
membrane while others cannot.
The Cell Membrane
 The cell membrane has proteins embedded in it.
 There are four main types of membrane proteins.
Cell-surface marker
 Enzymes
 Transport protein
 Receptor protein


Proteins have polar and nonpolar sections.
The polar sections of the protein attach to the polar heads.
 The nonpolar sections of the protein attach to the nonpolar tails.

The Cell Membrane
 Cell-surface markers identify
what type of cell it is.

Many cell-surface markers are
glycoproteins.


Glycoproteins are a combination of a
protein with a polysaccharide
attached.
Auto-immune diseases such as lupus
are caused by the body misidentifying the glycoprotein on a cell.

This causes the white blood cells to
attack the body’s own cells.
The Cell Membrane
 Enzymes are also embedded in the cell membrane.
 These membranes speed up chemical reaction within the cell.
 Transport proteins help substances move across the
cell membrane.


Some molecules are too big to move between the lipid bilayer,
and therefore have to be allowed into a cell through the
transport protein.
Some transport proteins require ATP to open.
The Cell Membrane
 Chemical signals are transmitted across the cell
membrane.


Receptors bind with ligands and change shape.
There are two types of receptors.
The Cell Membrane
 Chemical signals are transmitted across the cell
membrane.


Receptors bind with ligands and change shape.
There are two types of receptors.

intracellular receptor
The Cell Membrane
 Chemical signals are transmitted across the cell
membrane.


Receptors bind with ligands and change shape.
There are two types of receptors.
intracellular receptor
 membrane receptor
