1. KEY CONCEPT The ____ ________ is a _______ that _________ a cell from the ________ __________.

2. Cell membranes are composed of ___ ____________ ______.
The cell membrane has ___ _____ _________.
forms a ________ between ______ and _______ of the ___
controls _______ of _________
cell membrane
outside cell
inside cell

3. Cell membranes are composed of two phospholipid layers.
The cell membrane is made of a phospholipid bilayer.
There are other _________ ________ in the ________.
The _____ ______ _____ describes the membrane.
cell membrane
protein
cholesterol
carbohydrate
chain
protein channel

4. Cell membranes are composed of two phospholipid layers.
The cell membrane is ___________ _________.
Some molecules can cross the membrane while others cannot.

5. _________ _______ are ___________ across the ____ ________.
_________ bind with _______ and change _____.
There are ___ _____ of ________.
____________ receptor

6. Chemical signals are transmitted across the cell membrane.
Receptors bind with ligands and change shape.
There are two types of receptors.
intracellular receptor
________ receptor