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.
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.