3. WhaT is cell ?
Cell is structural
and functional
unit of life
4. discovery of The cell
Robert Hooke – first to see and
identify cork ‘cells’ .
5. shape and size of
The cells
Some cells can change their
shapes like amoeba , WBC but
plants and animals cells have
almost fixed shapes .
Smallest cell =PPLG(mycoplasma)
Largest cell = ostrich egg .
Longest animal cell = nerve cell .
6. cells organisms are
classified as :-
Unicellular :- made of single cell.
example :- amoeba ,paramecium.
Multicellular :- made up of
many cells .
Examples :- plants , animals and
fungi .
9. cell is basic uniT of life . Why ?
oIt is the smallest living unit
which makess all body .
oDivison of labour – cell usually
possesses a number of components
called cell organelles .
oEach of organelle perform
functions
i. Clearing waste material
ii. Protein synthesis
10. cell made up of WhaT ?
A typical cell is made up of
mainly three parts :-
1)Nucleus
2)Cytoplasm
3)Cell membrane .
11. PlasmaPlasma membrane – cell membranemembrane – cell membrane
It is outermost delicate covering of cell .
It is also called selectively permeable
membrane or seme permeable membrane
because it allows entry of selective
substances only.
It is made up of a bi-lipid layer and
proteins.
12.
13. Functions:-
It provides shape to contents of cell .
It provides mechanical barriers to the
cells .
It selectively allows the movement of
substances in and out of the cells which
are useful for in functioning of cells .
ATP -> adenosie tri phosphate
14. DiFFusion
Movement of solute particles from higher
concentration to lower concentration is
called diffusion .
Example : exchange of gases during
respiration.
15. osmosis
The movement of solvent particles from
lower concentration to higher
concentration in presence of semi
permeable membrane is called osmosis.
example – absorption of water by
roots .
16. types oF osmotic solutions
1. Hypotonic : The solution which have
lower concentration than others .
2. Hypertonic :- The solution which have
higher concentration than others .
3. Isotonic :- The solution which have equal
concentration than others .
17. types oF osmosis
Endosmosis :- movement of water inside cell
is called endosmosis .
It takes place when cell is placed in low
concentration solution .
Exosmosis :- movement of water out from
the cell is called exosmosis .
It takes place when cell is placed in high
concentration solution .
18. cell wall
Rigid , semi elastic , semi transparent
and protective covering present outside
the plasma membrane in plant cells ,
fungi and prokaryotic .
Made up of cellulose in plants , fungal
cellulose and chitim in fungi .
19. Functions
It provides shapes to the cells .
It provides mechanical strength to plants .
Protects against pathogens and mechanical
injury .
Growth of the cell wall determines the
growth of cells .
Cell wall prevents bursting of cell on
endosmosis.
20. nucleus
1. It is dense protoplasmic body that
contains hereditary information
present in the cell .
2. It generally lies in central position .
3. In plants its lies toward periphery .
21.
22. chromatin material
• Thread like material made of DNA
and protein present in nucleus is known
as chromatin material .
23. chromosomes
Thread like structure which are formed by
condensation of chromatin during cell
division are called chromosomes they refer
as hereditary vehicles .
Chromosomes are made of DNA and
proteins .
24.
25. cytoplasm
It is a fluid present between nucleus
and cell membrane .
It contains number of special
organelles such as mitochondria , golgi
apparatus etc .
26. endoplasmic reticulum
it is a complex network of membrane bound
channels or sheets , tubules and vesicles .
It is connected to both nuclear membrane and
plasma membrane .
It has (i) cisternae ,(ii) tubules , (iii) vesicles .
It act as endoskeleton of cell .
There are two types of ER .
i. Rough ER
ii.Smooth ER .
27. smooth er
• Smooth ER mainly consist of tubules
and vesicles .
• Its surface is free from ribosomes .
• Functions :-
Synthesis and secretes lipids and
steroids .
28. rough e.r.
It mainly consist of cisternae , tubules and
vesicles.
Its contains ribosome on its surface .
Function
I. To synthesis and secrete protein.
29. golgi apparatus
• It is double membrane structure made up ofIt is double membrane structure made up of
cisternae , vacuoles and vesicles .cisternae , vacuoles and vesicles .
FUNCTIONS :-FUNCTIONS :-
Golgi apparatus is involved in repair and synthesisGolgi apparatus is involved in repair and synthesis
of cell membrane .of cell membrane .
Lysosomes are formed by Golgi apparatus .Lysosomes are formed by Golgi apparatus .
All types of substances which are to be excreted areAll types of substances which are to be excreted are
packed in vesicle by Golgi apparatus for passage topacked in vesicle by Golgi apparatus for passage to
the outside.the outside.
Takes part in storage, modification and packagingTakes part in storage, modification and packaging
of various biochemical produced by differentof various biochemical produced by different
component of the cells .component of the cells .
30.
31. lysosomeslysosomes
They are also known as sucidal bags .
They are found in animal cells they lack in
plant cell .
In damaged cell , lysosome burst to release
enzymes for digestion of cellular components .
Functions :-
i. Destruction of foreign particles .
ii.Intracellular digestion .
iii.Removal of cell debris .
33. mitochondria
• It is rod shaped double membrane
organelle .
• Function :-
• It is also called power house of a cell
because in mitochondria energy id
produced through respiration and stored
in the form of ATP .
35. PLaStidS
Plastids are double membrane structure
present only in plant cell which synthesis
and store organic substances .
There are three types of plastids :-
1.Chloroplast (green color )
2.Chromoplast (other than green )
3.Leucoplast (colorless )
36. PLaStidS ( functionS )
• Chromoplast provide color to fruits and flowers .
• Leucoplast take part in protein , starch and oil .
• Chloroplast trap solar energy to manufacture
food through photosynthesis .
• Chloroplast are also known as kitchen of the plant
because in chloroplast food is synthesis through
photosynthesis .
38. VacuoLES -/StorE houSE of cELL
In plant cell vacuoles are large sized and in
animal cell vacuoles are small in size .
In plant cell vacuole is full of cell sap it
provides rigidity and turgidity to plant cell .
Many important substances such as protein ,
ammino acids and sugar are stored in
vacuoles .
