A. Cell wall: The cell wall is the outermost layer of living cell. The thickness of cell wall is approximately 70 Ao
Functions: The cell wall diffuse substances from inside to outside and viceversa
B. Nucleus: This is largest part of the cell located at center. It contains two parts.
- Nucleolus: It is a coiled filamentous structure contains number of granules. Nucleolus functions as a synthesis of Ribonucleic acid
- Chromatin: It consists of DNA (Deoxy Ribonucleic acid) and proteins. Chromatin functions to carry genetic information from one generation to another generation.
C. Cytoplasm: Cytoplasm present in between cell wall and nucleus. All cell organelles including endoplasmic reticulum, golgi apparatus, lysosomes, mitochondria and centrosomes present in the cytoplasm.
D. Microsomes: These are tiny cell organelles that are present inside the cell. These contain two components i.e ribosomes and granulated matrix.
- Ribosomes : It is responsible for protein synthesis
- Granulated matrix: It contains oxidases and catalases to generate hydrogen peroxide and water (H2O) respectively.
E. Endoplasmic reticulum: It contains two membranes which are separated by a space. They are
- Granular or rough surface endoplasmic reticulum: It contain ribosomes that are responsible in protein synthesis.
- Agranular/ Smooth surface endoplasmic reticulum: It is responsible for synthesis of fatty acids and steroids.
F. Golgi apparatus: These are cup shaped structures containing vesicles that are responsible for the concentration of proteins prior to their secretion.
G. Mitochondria: It contains two layers i.e., outer layer is smooth and inner layer is folded into sheet of tubules called cristae. Both layers are enclosed by a center cavity called matrix. These are responsible for the cellular oxidation. These are also called as Power house of cell.
H. Lysosomes: These are spherical and oval shaped part in the cell . It contains hydrolytic enzymes that function engulfment of bacteria and cell debris. So these are also called as Suicide bags.
I. Centrosome: These are small rod shaped bodies. They play an important role in cell division.
J. Microtubules: These are straight hollow cylinders shaped organelles that are responsible for maintaining cell shape.