CELL WALL AND PLASMA MEMBRANE

By Er. Anoop Dhiman5 Comments

     CLASS-09  |   CHAPTER-5  | CELL: THE FUNDAMENTAL UNIT OF LIFE   

CELL WALL AND PLASMA MEMBRANE

    (a) CELL WALL

  • Cell wall is thick and hard covering of the cell.
  • It is made up of cellulose.
  • It is non-living part of the cell.
  • It is permeable to most of the substance.
  • Cell wall is present in the plant cell and in the cells of some bacteria and fungi.

        FUNCTIONS CELL WALL

  1. Cell wall provide shape to the cell.
  2.  It protect the plasma membrane.
  3. It prevent excess loss of water.
  4. It helps in the transportation of various substances in and out of the cell.

(b) PLASMA MEMBRANE

  • Plasma membrane is the covering of the cell that separate the contents of the cell from its external environment.
  • It is very thin delicate & selectively permeable membrane.
  • It is living part of the cell.
  • It is composed of lipids and proteins.

 

     FUNCTIONS OF PLASMA MEMBRANE

  1. Plasma membrane provide container to the cytoplasm.
  2. As it is selectively permeable membrane therefore it allow only limited substances to move in and out of the cell.

DIFFERENCES BETWEEN CELL WALL AND PLASMA MEMBRANE

CELL WALL PLASMA MEMBRANE
1. It is thick and hard covering of the cell.  1. It is thin and delicate covering of cell
2. It is non-living part of a cell. 2.It is living part of the cell.
3. It is composed of cellulose. 3. It is composed of Lipids and proteins.
4. It is present only in plant cells. 4. It is present in plants as well as in animal cells.
5. It is permeable to most of the substances. 5. It is semi-permeable and allow only limited substances to move in and out of the cell.

ANSWER THE FOLLOWING QUESTIONS IN COMMENT BOX..

  1. Cell wall is made up of …………………
  2. Plasma membrane is made up of ………………….
  3. Cell wall is present only in ……………….cells
  4. Why plasma membrane is called semipermeable membrane.