Summary Topic 2 Cell Membrane Structure

Cell membranes


Function : -
transport between cells



E Selectively permeable - it chooses which molecules in and out
-




go
S.I units
partially permeable >

only
let certain molecules through
- -




Compartmentalisation
-




↳ keeps inside the cell
everything
Imitochondria are membrane bound X membrane bound organelles)
and
signalling
-


Communication

↳ receptors -
hormones




Phospholipids



I
Chemical

hydrophilic (polar group
7
- Phosphoester bond Phospho
head diester
group


phosphate
phosphate head bond

>
-
phosphoester bond


glycero ↳




I
= ester bond


hydrophobic (non-polare


2
1
x
fatty acid chains

saturated

I monounsaturated




Polar and non-polar ends
↳ Amphiphilic/Amphiphatic

The phosphate is polar the covalent bonds between
group
as


phosphorous and Oxygen is unbalanced
.
Oxygen is more
electronegative
electrons closer and make it delta and
so are
negative
phosphorous delta positive . In a
phospholipid bilayer phosphate heads
bonds
face inwards and outwards
interacting
with water
forming hydrogen .