Define a cell in brief?
it was discovered by Robert hooke
Answers
Answered by
1
The cell is the structuctral unit of life because it is the tiniest living unit which have life. Our body is made up of trillions of cells. A cell is the building block of life. And a cell is also known as Functional unit of life because it is capable for doing any functions of our body such as excretion, respiration, reproduction etc....
Answered by
5
→ Cells are the structural and functional unit of life.
* All living organisms are made up of cell. That's why cell is known as structural unit of life.
* A single cell can perform all life functions with the help of it's components. Therefore it is known as functional unit of life.
→ Robert Hooke first discovered the cell in 1665.
* He prepared a thin slice of cork and observed it under self made microscope. He saw some box like structures which he named as cell.
→ Anton Von Leeuwenhoek first saw the living cell and also first describe the living cell.
→ Cells can replicate independently.
→ It contain hereditary information due to presence of nucleus or nucleoid.
→ All organisms are made up of cells. Organisms with single cells are known as unicellular organisms. And organisms with multiple cells are known as multicellular organisms.
→ Cells size ranges from 1 - 100 μm.
→ Mycoplasmas, is the shortest cell (0.3 μm) and ostrich egg and nerve cells are the largest cell.
→ Cells are in different shapes. Their shape vary with their function. They may be cuboid, thread like, disc like etc.
→ Cells are of two types namely; Eukaryotic an Prokayotic cells.
a) Eukaryotic cells :-
* These are generally large in size.
* Nuclear region is well defined and surrounded by a nuclear membrane.
* These are multicellular.
* Single chromosome are present.
* Member bound cell organelles are present such as mitochondria, endoplasmic reticulum, golgi appartus etc.
* DNA is linear.
* Cell divides by binary fission and budding.
* Ex :- Human beings, plants etc.
b) Prokayotic cells :-
* These are smaller in size.
* Nuclear region is not well defined and not surrounded by a nuclear membrane.
* These are unicellular.
* More than one chromosomes are present in it.
* Membrane bound cell organelles are absent such as mitochondria, endoplasmic reticulum, golgi appartus etc.
* DNA is circular.
* Cell divides by mitosis and meiosis.
* Ex :- Bacteria, blue-green algae etc.
__________________________________
Similar questions
✔️ it is called the functional and fundamental unit of life because our body is made up of small cells and all the works of our body internal and external are performed by the cell.
✔️ it is the building block of the body.
✔️ Every cell derives from pre-existing cell.