The cell is the fundamental and structural unit of life and cells are often called the "building blocks of life".
Organisms can be classified as unicellular (consisting of a single cell, ex: bacteria) or multicellular (consisting more than one cell, ex: plants and animals).
- Plasma membrane
- Cell wall
The cell is the basic structural, functional, and biological unit of all known living organisms. A cell is the smallest unit of life that can replicate independently.
Organisms that are made up of a single cell and perform all their vital activities, like reproduction, locomotion, and digestion, are called unicellular organisms.
Example: Bacteria, Paramecium.
Organisms that are made up of more than one cell are called multicellular organisms.
Example: Plants, Animals.
Larger an organism, greater is the number of cells in its body.
Cells are differently shaped based on the functions they perform, but all contain the 3 basic and essential parts,
- Cell membrane
The structure of the Cell:
- Nucleus: The nucleus is a membrane bound structure that contains the cell's hereditary information and controls the cell's growth and reproduction.
- Plasma membrane: The plasma or cell membrane is a thin semi-permeable membrane that surrounds the cytoplasm of a cell, enclosing its contents. Its function is to protect the integrity of the interior of the cell by allowing certain substances into the cell while keeping other substances out.
- Cytoplasm: Cytoplasm is the clear, gel-like substance outside the nucleus of the cell of plants and animals.
- Cell wall: The cell wall is the protective, semi-permeable outermost layer of a plant cell which gives the cell strength, protection and structure.