The cytoskeleton is a structural framework in the cytoplasm made up of microfilaments, intermediate filaments, and microtubules, which enable cell shape, movement, and motility. Microfilaments are involved in cell shape and division, intermediate filaments provide mechanical support, and microtubules facilitate intracellular transport and form cilia and flagella for locomotion. Together, these elements form the muscle and skeleton of the cell, playing critical roles in its function.

1. The Cytoskeleton
Shareeka Joana Ngilay

2. What is Cytoskeleton?
Cytoplasm contains a
complex network of
filaments and microtubules
which form a structural
framework known as
CYTOSKELETON.

4. Cells need (cyto) skeleton to:
*create shape
*change shape
*allow movement
Dynamic!
Cytoskeleton: The skeleton and muscle of a cell

5. Three main kinds of fibers make up
the CYTOSKELETON:
● MICROFILAMENT
● INTERMEDIATE FILAMENT
● MICROTUBULES

8. MICROFILAMENT
● Thinnest filament present
in the cytoskeleton in
cytoplasm of eukaryotic cell.
● Give the cell its shape
and enable cell movement

9. MICROFILAMENT

12. FUNCTIONS OF MICROFILAMENT
Microfilaments play a role in
structure, cell motility, and cell
division. Microfilaments are made
of actin, and thus are involved in
muscle contraction as well as cell
division.

13. INTERMEDIATE FILAMENTS
● Made of variety of proteins,
including keratin, desmin and
vimentin
● 8 to 12 nanometer
● Composed of two anti
parallel dimer

14. INTERMEDIATE FILAMENTS

19. FUNCTIONS OF INTERMEDIATE FILAMENT
● provide mechanical support for
the plasma membrane where it comes
into contact with other cells or with
the extracellular matrix
● intermediate filaments do not
participate in cell motility.

20. MICROTUBULES
● Microtubules, the thickest fibers, are
hollow rods about 25 microns in
diameter.
● Microtubule fibers are made up of
the globular protein, tubulin, and they
grow or shrink as more tubulin molecules
are added or removed.

21. MICROTUBULES

25. Microtubules participate in the
intracellular transport of organelles
and vesicles.
FUNCTIONS OF MICROTUBULES

27. Microtubules are the central structural
supports in cilia and flagella.
The locomotive appendages of cell

28. Cilia
● minute hairlike organelles, identical in
structure to flagella, that line the surfaces
of certaincells and beat in rhythmic waves,
providing locomotion to ciliate protozoan a
nd moving liquids along internal epithelial
tissue in animals.

29. CILIA

32. FLAGELLA
● A slender threadlike structure,
esp. a microscopic whiplike
appendage that enables many
protozoa, bacteria, spermatozoa,
etc., to swim.

33. FLAGELLA

34. FLAGELLA

37. Thank you