Question

2. What are the physical properties that constitute the Membrane, all structures associated with it?

3. What are the proteins and their specific functions within the membrane?

Answer 1

2. Physical properties of membrane depend on composition of mostly lipids
A)Phase transitions between fluid & gel
outside of rafts, membranes are usually fluid
Fluid phase normally has high degree of motional freedom
around C—C bonds in fatty acids.
Gel phase: motional freedom lower by orders of magnitude
B). Fluid-gel transition ≈ liquid-solid transition
C) Non-bilayer phases exist like micelle
These are important for membrane fusion, also environmental stress responses.

3. Proteins associated with the lipid membranes can be called as a membrae proteins. They include 1) integral proteins ( which are embedded within the lipid bilayer ) and 2) peripheral proteins ( which are attached to the integral proteins or lipid bilayer). They can be fibrous, soluble or disordered proteins.

functions:

a. They help in signal translocation between cell`s external and internal environments.

b. They transport ions and molecules across the membranes and are specifically called transport proteins.

c.They can act as enzymes like oxidoreductase, transferases or hydrolases.

d.They also function as cell adhesion molecules allowing cells to identify each other and interact like proteins involved in immune response.

Indegral protrin ipd bilayen Periyheral rotin CS Scanned with CamScanner