Explain the variation of size of cells.
Cells vary in their size. Some cells are very small like bacterial cell whose size is about 0.5 micrometre. Nerve cell is about 1 metre long. Ostrich egg is the largest cell measuring 170 mm ×130 mm.
Write the functions of cytoplasm.
Functions of cytoplasm are :
(i) It is a physical basis of all metabolic activities.
(ii) Various cell organelles perform specific functions in the cytoplasm.
(iii) It provides turgidity.
Differentiate between prokaryotic cell and eukaryotic cell.
Prokaryotic Cell |
Eukaryotic Cell |
1. Nucleus is not bound by a nuclear membrane 2. Cell size is generally small (1–10 μm). |
1. Nucleus is bound by a nuclear membrane. 2. Cell is generally large (5–100 μm). |
Write any two functions of protoplasm.
Two functions of protoplasm
(i) It controls all the functions of a cell .
(ii) It is the house for all the cell organelles..
Write the functions of mitochondria, golgi bodies and ribosomes.
Mitochondria : It performs the function of respiration and provides the cell with energy. It is called the power house of cell.
Golgi bodies : These collect and distribute substances made in cell, synthesis and secretions of many materials.
Ribosomes : They help in the synthesis of proteins.