write a note on structure of a cell? plz help me
Answers
Heya!!
✍A cell is composed of 3 different parts:-
●Cell membrane
●Cytoplasm
●Nucleus
✍Cell is the structural and functional unit of life which divides and differenciates to form tissues and then organs.
Cells were discovered by Robert Hooke. In 1665, the English scientist Robert Hooke observed slices of cork (bark of tree) which is part of bark of a tree, under a simple magnifying device. He noticed partitioned boxes or compartments in the cork slice.
The instrument used to see cells is microscope.
Microscope is an instrument which is used to magnify the very small objects, which cannot be seen with the naked eye. It was discovered by Anton van Leeuwenhoek. The Ancient microscope is the microscope which discover the cell.
Types of cell
There are two types of cell which are as follows:
Prokaryotic Cells
The cells having nuclear material without nuclear membrane are termed as prokaryotic cells. The organisms with these kinds of cells are called prokaryotes. “Pro” means primitive and “karyon” means nucleus. Examples: bacteria and blue green algae.
Eukaryotic cells
The cells having well organised nucleus with a nuclear membrane are designated as eukaryotic cells. All organisms other than bacteria and blue green algae are called Eukaryotes. “Eu” means true and “karyon” means nucleus.
Cells have Three Basic Characteristics
Cell Membrane
Genetic Material
Metabolic Machinery
The shape of the cell depends upon its function. The shape of the cell may change or remain same.
For example: The cells which are helpful in protection have different characteristics and similarly the cells involved in circulation have different characteristics.
Different shapes of Cell are as follows:
Spindle like
Flat
Oval
Irregular
Disc like
Round
Cylindrical
Cube-like
Elongated
Branched