Plasma Membrane Research Paper

INTRODUCTION

The plasma membrane is the boundary between the cell and its environment. It regulates what enters and exits the cell. Cells must maintain an appropriate amount of molecules to function inside them. They must also have a way to keep things out or to allow things to enter. This is the job of the plasma membrane. The plasma membrane is like the guard must inspect those who enter and those who leave to make sure that only the people and things needed in the community are there.

A plasma membrane encloses every type of cell, both prokaryotic and eukaryotic cells. It physically separates the cytoplasm from the surrounding cellular environment. Plasma membrane is a ultrathin, elastic, living, dynamic and selective transport- barrier.

The term cell membrane was coined by C.Nageli and C.Cramer in 1855 and the term plasmalemma has been given by J.Q.Plowe in 1931.

PLASMA MEMBRANE DEFINITION

Plasma membrane can be defined as a biological membrane or an outer membrane of a cell, which is composed of two layers of phospholipids and embedded with proteins. It is a thin semi permeable membrane layer, which surrounds the cytoplasm and other constituents of the cell.

PLASMA MEMBRANE STRUCTURE

1. It is the boundary, which separates the living cell from their non-living surroundings.

2. It is the phospholipids bilayers.

3. Plasma membrane is an amphibatic, which contains both hydrophilic heads and hydrophobic

It separates the content of the cell from its outside enviroment and it regulates what enters and exitsthe cell.

2. Plasma membrane plays a vital role in protecting the integrity of the interior of the cell by allowing only selected substances into the cell and keeping other substances out.

3. It also serves as a base of attachment for the cytoskeleton in some organisms and the cell wall in others.Thus the cell and helps in maintaining the shape of the cell.

4. The cell membrane is primarily composed of proteeins and lipids.While lipids help to give their flexibility and proteins monitor and maintain the cell's chemical climate and assist in the transfer of molecules across the membrane.

PROKARYOTIC PLASMA MEMBRANE

The eukaryotic plasma membrane is a phospholipids bilayer with embedded protiens. In the middle of the bilayer, the fatty acids of the phospholipids are found, which is called as hydrophobic region. Prokaryotic cells can have multiple plasma membranes. In these organisms plasma membranes are responsible for controlling the entry and exit of the