practical

2. • Pro : false (primitive )
• Karyotes : nucleusProkaryotes
• Eu : True
• Karyotes : nucleusEukaryotes

3. (I) Structure of prokaryotic cell

4. Cell Wall
*Outer covering of most cells
that protects the bacterial cell
and gives it shape
*Composition: Peptidoglycan
Prokaryotic Cell Structures:

5. Prokaryotic Cell Structures:
Cell
Membrane
Surrounds the
cell's cytoplasm
Allow exit and
entry of small
molecule.
Entrance

6. Cytoplasm
(cytosol)
* Contain genetic
material and other
organells
Prokaryotic Cell Structures:

7. Capsule
additional
outer
covering
protects
the cell
Prokaryotic Cell Structures:
Pili
Hair-like
structures
on the
surface of
the cell that
attach to
other
bacterial
cells
Flagella
Long, whip-
like
protrusion
that aids in
cellular
locomotion

9. (II) Structure of eukaryotic cell

10. 1. Cell Wall
 Found in prokaryotes, plants, and algae
 Rigid, protective barrier
 Located outside of the cell membrane

11. 2. Cell Membrane
Boundary of the cell…. Protective.. Control
passage of substances into and out of the
cell
Made of a phospholipid bilayer

12. 3. Nucleus
• Contains most of genetic material
(DNA in complex with protein)
• Function : maintain integrity of
these genes and to control
activities of the cell

13. Nucleus
A) nuclear envelope :
•Encloses and separates the cell's
genetic material from the
surrounding cytoplasm.

14. Nucleus
B) Nuclear pores :
•Allowing passage of small water-soluble
molecules, preventing larger molecules,
from entering or exiting the nucleus.
C) Nucleolus:
• Makes Ribosomes

15. 4. Ribosome
Site of protein synthesis
Produced in called the nucleolus.
Found attached to rough ER
(Bound ribosome)
or
free in cytosol
(Free ribosome)

16. 5. Endoplasmic Reticulum
Rough ER:
studded with ribosomes;
it makes proteins
Smooth ER:
no ribosomes;
it makes lipids

17. 6. Golgi Apparatus
Stores, modifies and packages
proteins
Molecules transported to and
from the Golgi by means of
vesicles

18. 7. Lysosome
• Contain digestive enzymes that break
down wastes
• Protects cell from foreign particles that
enter the cell by destroying them.

19. 8. Mitochondria
(The power house of the cell)
 The organelle that releases energy in the
cell.
 They use nutrients and oxygen to produce a
high energy molecule know as ATP
(Adenosine Triphosphate) in aerobic
respiration.
 Mitochondria are very abundant in cells
that require lots of energy.
Ex:- Brain, Muscle

20. Mitochondria

21. 9. chloroplast
 Present in all living plant cells
 Algae also containing them.
 Chloroplasts' main role is to conduct photosynthesis,
due to the presence of chlorophyll

22. 10. Peroxisome
 A major function of the peroxisome is the breakdown of
very long chain fatty acids.
 Peroxisomes contain enzymes (oxidases and catalase).
RH2 + O2 R + H2O2
 Catalase eliminates the poisonous hydrogen peroxide
by breaking it down by means of the peroxidation
reaction.
2H2O2 2H2O + O2
oxidase
catalase

23.  This reaction is important in liver and kidney cells, where the
peroxisomes detoxify various toxic substances that enter the
blood.
 Experiment
 A small amount of yeast powder is mixed in a test tube with
H2O2
EFFERVESCENCE (foam formation)
Explain???????

24. EFFERVESCENCE (foam formation) after mixing
a small amount of yeast powder with H2O2 in a beaker