2. OUTLINE
 Golgi apparatus
 Cytoskeleton
 Smooth Endoplasmic Reticulum
 Lysosome
 Centriole

3. GOLGI APPARATUS
 It is a membranous complex of
vesicles, vacuoles, and
flattened sacs in the cytoplasm
of cells which is involved in
intracellular secretion and
transport.
 It is found in all eukaryotic
cells.
 It is sometime called as Golgi
Body or Golgi Complex.

4. DISCOVERY
 Golgi apparatus was discovered by
Camillo Golgi in 1898.
 He developed a method that stained
it intensely and made possible the
demonstration of its occurrence in a
wide variety of cell types.
 This method is known as Golgi
Staining.

5. Structure and Composition
 Golgi apparatus is composed of
stacks of membrane-bound
structures known as Cisternae.
 A cisterna (plural cisternae)
comprises a flattened
membrane disk that makes up
the Golgi apparatus.
 Golgi apparatus usually has 6-7
cisternae.
 A complex network of tubules
and vesicles is located at the
edges of these cisternae.

6. Structure and Composition
The cisternae stack has two faces.
 Trans-Golgi
 Cis-Golgi

7. FUNCTIONS
 Golgi apparatus is concerned with cell secretion.
 It involves in the creation of lysosomes.
 The most important function of this apparatus is to modify the
proteins and lipids by adding carbohydrates and converting
them into glycoproteins or glycolipids.

8. CYTOSEKELTON
 Cytoplasm contains a
complex network of filaments
and microtubules which form
a structural framework known
as Cytoskeleton.

9. Structure and Composition
 The primary components
of the cytoskeleton are
microtubules,
microfilaments and
intermediate filaments.

10. Structure and Composition
 Microtubules:
Microtubules are long, unbranched, slender tubulin protein
structures. One very important function of it is their role in the
assembly and disassembly of the spindle structure during
mitosis.
 Intermediate filaments:
They have diameter in b/w those of microtubules &
microfilaments. They play role in the maintenance of cell shape.

11. Structure and Composition
 Microfilaments:
They are considerably more slender cylinders made up
of actin protein. They involved in internal cell motion.

13. FUNCTIONS
 It provides structural support to the cell.
 It involves in cell motility, cell division and regulation.
 It plays an important role in intracellular transport.
 It often protects the cell.

14. ENDOPLASMIC RETICULUM
 It is a extensive network of
folded membranes that
extends from the nuclear
envelope to which it is
connected throughout the
cytoplasm.

15. Endoplasmic Reticulum
 Endoplasmic Reticulum is divided into two
sub-compartments.
• Smooth endoplasmic reticulum
• Rough endoplasmic reticulum

16. SMOOTH ENDOPLASMIC
RETICULUM
 In some cell it is responsible
for transmission of impulses
(muscle cell, nerve cell).
 It plays an important role in
the transport of materials
from one part of the cell to
the other.

17. Structure and Composition
 It is a branching tube
structure which is held
by cytoskeleton.
 In smooth endoplasmic
reticulum ribosomes are
not attached, therefore
its surface is smooth.
 It contains collection of
enzymes.

18. FUNCTIONS
 Synthesis of fatty acids and steroid hormones
such as estrogens and testosterone.
 Detoxification in the liver of a wide variety of
organic compounds, including barbiturates & ethanol.
 Metabolize different types of molecules particularly lipids.

19. LYSOSOME
 Lysosomes are cytoplasmic
organelles.
 Lysosome founds in almost all
eukaryotic cells.
 Lysosomes have digestive
enzymes.

20. LYSOSOME
 They are most abundant in those
animal cells which exhibit phagocytic
activity.

21. Structure and Composition
 They are bounded by a single
membrane and are simple sacs
rich in acid phosphates and
several other hydrolytic enzymes.
 The membrane acts as a
protective barrier that protects
the rest of the cell from the
enzymes that are contained
within the lysosome.

22. FUNCTIONS
 It is involved in the autophagy (self eating).
 Any foreign object that gains entry into the cell
is immediately engulfed by the lysosome and is
completely broken into simple digestible pieces.
 This process is known as phagocytosis (eating
process of a cell).

23. CENTRIOLE
 Hollow cylindrical organelles
present in animals and many
unicellular living organisms.
 Animal cells, cells of some
microorganisms and lower
plants contain two centrioles
located near the exterior
surface of the nucleus.
 These two centrioles are
collectively called as
centrosome.

24. Structure and Composition
 Centrioles are made up of nine
microtubule triplets.
 These microtubule triplet is made
up of tubulin protein.
 Centrioles are also the part of
cytoskeleton.

25. Structure and Composition
 The two centrioles are usually placed right angle to each
other.
 They are absent in higher plants.

26. FUNCTIONS
 They made spindle fibers during cell division.
 They play important role in the formation of cilia.
 They involves in the location of furrowing during cell division.