The document discusses the cell, which is the fundamental unit of life. It describes key discoveries in cell history, such as Hooke discovering dead cells in 1665 and Leeuwenhoek discovering living cells in 1674. The document outlines the main parts of plant and animal cells, including the cell membrane, nucleus, cytoplasm, mitochondria, endoplasmic reticulum, Golgi apparatus, and lysosomes. It explains the differences between prokaryotic and eukaryotic cells and differences in plant and animal cells, such as plant cells containing a cell wall.

2. Class -9
The fundamental unit of life

3. What is cell?
The structural and fundamental unit of
life is known as cell.

4. Robert Hooke was the person who invented
the first dead cell in 1665 through a cork of
tree and noticed the honey-comb structure
and named it has Cell ( Latin word meaning
little room)

5. •1665- Robert Hooke (dead cell- tree cork)
•1674- Anton van Leeuwenhoek (living cell
pond water)
•1931- Robert brown (nucleus)
•1839- Purkinje ( Protoplasm)
•1838-1839 – Schwann and Schleiden( cell
theory)
•1855 Virchow (expanded cell theory)

6. •The organism which is made up of 1 cell is
known as unicellular organism.
•The organism which is made up of 2 or more
cell is known as multicellular organism.

7. •There are more
types of cell
Smooth muscle cell
Blood cell
Nerve cell
Ovum
Fat cell
Sperm cell

8. •In the unicellular
organism all the
works are done by a
single cell.
•In multicellular
organism the
division of labor
takes place.

9. •There are
different
parts of cell
these parts of
cell are
known as
Organelles.

10. Plasma membrane
• The plasma membrane separates the cell content from the
external environment.
• The plasma membrane is the outermost covering of the cell
which allows only certain objects in and out of the cell thus
cell membrane or plasma membrane is known as selectively
permeable membrane
• Plasma membrane is flexible and made up of organic
materials called proteins and lipids

11. Osmosis and Diffusion
•The movement of particles from higher
concentration area to lower concentration
through a semi-permeable membrane is
called as osmosis.
•The movement of particles from higher
concentration area to lower concentration
is called as diffusion.

13. Endocytosis
•The intake or engulf of
food by the amoeba is
called as endocytosis

14. Cell Wall
• Cell wall is another protection
layer which present in the plant
cell.
• Cell wall is made up of cellulose.
• It provides the shape to the cell.
• When living cell loses its water
the contraction of contents
from cell is known as
Plasmolysis

15. •When the cell loses its water the cell swell,
building pressure upon the cell wall, the cell
wall gives pressure to the cell. Such cells can
withstand much greater changes in
surrounding.

16. NUCLEUS
• Nucleus is the brain of cell.
• It controls all activities of cell.
• It is covered by double-layered membrane known as
nuclear membrane.
• The nuclear membrane contains pore which
germinates the objects in and out nucleus.
• It contains chromosome.

17. Functions
•The nucleus is responsible for the
inheritance of materials from parent to
offspring.
•It allows Chemical activities.
•It plays an vital in cell division.

18. Prokaryotic and Eukaryotic cell
•Prokaryotic cell contains
undefined nucleus.
•Eukaryotic cell contain well
defined nucleus.

19. CYTOPLASM
• Cytoplasm is the fluid substance
which is present in the cell.
• It is a fluid substance which Is
present in cell.
• It helps to fix the organelles.
• It gives shape to the cell.

20. Endoplasmic Reticulum
•It is interconnected network of flatterned
membrane enclosed sacs called cisternae.
•There are two types of endoplasmic reticulum
Rough endoplasmic reticulum
Smooth endoplasmic reticulum
•Close connection with nucleus.
•Present only in eukaryotic cell.

22. • Rough endoplasmic reticulum contains ribosomes which helps in
preparation of proteins
• Smooth endoplasmic reticulum helps in preparation of Fats and
lipid molecules.
• Some of the proteins and lipids help to construct the plasma
membrane is process is known as Membrane biogenesis.
• Some of the proteins and lipids acts as enzymes and hormones.
• It helps to transfer of materials within cytoplasm or from
cytoplasm to nucleus.
• It forms cytoplasmic framework which works or give surface to bio-
chemical activities.
• SER detoxifies the poisons and drugs

23. Golgi Apparatus

24. •It stores, modifies, Package of vesicles.
•It forms cell plate during cell division.
•Formation of complex sugar into simple sugars.
•Secretory proteins and lipids are packed and
secretes through exocytosis.
•Formation of lysosomes.

25. LYSOSOMES
• Lysosome are membrane bound sacs with powerful
enzymes.
• It helps in intracellular and extracellular digestion.
• It destroy any foreign materials which enters cell.
• They bring self destruction by releasing powerful
enzymes thus called as suicidal bags.

26. Mitochondria
•It is double layered
membrenel structure.
•It is known as power house
of cell.
•The inner membrane is
folded by which the inner
surface area will increase.

27. • The important functions of mitochondria are
deoxidation, dehydration and oxidative
phosphorylation.
• During biological oxidation of carbohydrates and fats
,the large amount of energy is utilized by
mitochondria in form of ATP molecules.
• Mitochondria is a strange organelle because it
contains its own DNA and Ribosome.