The Cell

Answer

A cell is the structural and functional unit of all living organisms (except viruses, some bacteria, etc.). It is called the basic unit of life because all metabolic activities like respiration, nutri…

Answer

The cell wall is a non-living, freely permeable structure made mainly of cellulose. It is present only in plant cells and is situated outside the cell membrane. It maintains cell shape, provides rigid…

Answer

Cell Wall: Non-living, freely permeable, made of cellulose, present only in plants, provides rigidity. Cell Membrane: Living, selectively permeable, made of lipid and protein, present in all cells, se…

Answer

Cytoplasm is a crystallo-colloidal solution present between the cell membrane and nucleus. It contains carbohydrates, proteins, fats, vitamins, minerals dissolved in water, enzymes for metabolic react…

Answer

Rough ER has ribosomes attached to its surface, giving it a rough appearance, and is involved in protein synthesis. Smooth ER lacks ribosomes, appears smooth, and is involved in lipid synthesis and de…

Answer

Ribosomes are the smallest cell organelles made of RNA and protein, not bounded by membrane. They can be attached to ER or free in cytoplasm. Each ribosome has two subunits (one big, one small). Their…

Answer

Golgi apparatus consists of flattened sac-like structures stacked one above the other (in animals) or diffused (dictyosome in plants). Functions include: formation and secretion of enzymes and hormone…

Answer

Lysosomes are called 'suicide bags' because they contain hydrolytic enzymes that can digest cellular components. When the cell is damaged or old, lysosomes release these enzymes to break down the cell…