Cell Structure

2. CONTENTS
 What is a cell?
 Discovery of the cell
 Parts of a cell
 Cell membrane and cell wall

3. WHAT IS A CELL?
A cell, as it is defined , is the basic structural and functional unit of any living
entity. It is the fundamental and the 1st living component of any body whether
plant or animal.
Although, defined as ‘a basic unit’ , its working is very complex and surprising
that such a small living body is working in various different ways to keep a whole
body alive.
The cell indeed is very small measuring from around 50 micrometres to 100
micrometres.
In the upcoming , we will learn more about this fascinating yet complex unit of
life.

4. Discovery of the cell
• The cell was discovered by an
English polymath Robert Hooke in
1665 who observed dead slices of
cork in his self constructed
microscope. Through his
microscope he saw ‘empty lumen’
and box like structure. He named
the term ‘cell’ to the box like
structure meaning ‘room’ in Latin.
He drew whatever he could see in
his book “Micrographia.” What
Hooke saw were actually dead
cells.

5. Parts of a cell
The basic parts of the cell, in
order, constitute of , cell
membrane , cytoplasm, and the
nucleus.
‘Protoplasm’.(Proto= first and
plasm= something molded), Is
formed by the cytoplasm and
nucleus . Together they form the
living components of the cell.

6. Cell membrane and cell wall
Cell membrane
• Cell membrane is a semi-
permeable porus membrane
that provides an outer covering
to a cell and separates it from its
surrounding medium. It is made
up of fats, proteins and lipids. It
is present in both plant and
animal cells.
Cell wall
• Cell wall is a freely permeable
rigid outer covering that is only
present in plant cell,it is made
up of cellulose. The prescence of
cell wall provides the plant with
a support system that allows it
to stand upright.