2.1 Cell Structure and Function

Theory of Cell

  1. The cell is the basic unit or building block for all living organisms.
  2. All organisms are made up of one or more cells .
  3. Cells are the fundamental and structural unit of life.
  4. A cell is made up of a plasma membrane which contains protoplasm.
  5. Protoplasm is made up of cytoplasm and a nucleus.
  6. A cell consist of the non-organelle structure the organelle structure.

Non-organelle/Organelle Structures of Cell

  1. The non organelle structure of a cell include
    1. Plasma membrane
    2. Cytoplasm
    3. Cell wall (plant cell only)
  2. Whereas the organelle structure of a cell include
    1. Nucleus
    2. Endoplasmic Recticulum
    3. Mitochondrion
    4. Ribosom
    5. Golgi apparatus
    6. Vacuole
    7. Chloroplast (plant cell only)

    Structure of an Animal Cell


    1. Each animal cell is enclosed by a plasma membrane.
    2. Within the plasma membrane is the protoplasm which consists of the cytoplasm and a nucleus.
    3. Animal cells do not have regular shapes.
    (This file is shared under GNU Share Document Licence from  Wikipedia)


    Structure of a Plant Cell


    1. Each plant cell is enclosed by a plasma membrane which is protected by a cell wall.
    2. Again, within the plasma membrane has a nucleus and cytoplasm.
    3. Unlike animal cell, most plant cells have chloroplasts which contain chlorophyll.
    4. Also, a mature plant cell may have a large vacuole which contains cell sap.
    5. Plant cells have a fixed shape because they have cell walls.
    (Onion Cell)