1. The Cytoskeleton, CELL SHAPE AND MOTILITY
JAN MUHAMMAD

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

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

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

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

8. MICROFILAMENT

11. 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. 

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

13. INTERMEDIATE FILAMENTS

15. 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.

16. 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. 

17. MICROTUBULES

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

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

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

22. CILIA

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

24. FLAGELLA

25. FLAGELLA

27. Thank you