Theory:

Centriole
Centrioles are organelles located in the cytoplasm. It is present only in animals cells and lacks a limiting membrane as well as DNA or RNA.  During cell division (mitosis and meiosis), centrioles form spindle microtubules.
 
Discovery: The word centriole comes from the Greek (Centrum - centre). Van Beneden discovered it in \(1887\), and Boveri explained on its structure in \(1888\).
 
Location: Except for mature mammalian RBCs, they are found in all animal cells and is absent in a plant cell.
Shape: They are barrel-shaped.
 
Position: They appear in pairs near the nucleus, generally at right angles to each other.
A centrosome is a type of organelle made up of two cylindrical structures known as centrioles.
Note:
  • The centrosphere is the region surrounding the pair of centrioles.
  • The centrosome is the cell's main microtubule organising centre.
Arrangement: Each centriole is made up of (nine \(9\) + \(0\)) tubulin protein peripheral fibrils that are uniformly spaced. The peripheral fibrils are all triplets. That's a ring with nine sets of triplets on the outside and none in the centre.
 
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Functions:
  • At the end of cell division, centrioles move to the poles and form asters that organise the spindle fibres during mitotic and meiotic cell division.
  • Cilia and flagella are formed by centriole in animal cells.
Cytoskeleton
The word cytoskeleton comes from the Greek (kytos - cells, skeleton - dried body). It extends from the nucleus to the plasma membrane.
The cytoskeleton is a complex network of filamentous protein fibres found in the cytoplasm.
Structure: It is a complex network of filaments and microtubules that forms a structural framework of a cell. During cell division, it's responsible for the segregation of chromosomes into two daughter cells.
 
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Cytoskeletal components
Important!
Cytoskeleton is often compared with bone and muscles of an animal.
Cytoskeletal fibres can be divided into the following categories
  • Microfilaments
  • Microtubules
  • Intermediate filaments
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Functions:
  • It helps to maintain the shape of a cell.
  • It controls the distribution and orientation of cell organelles.
  • It also aids cellular movement and intracellular transport.
Reference:
https://commons.wikimedia.org/wiki/File:0317_Cytoskeletal_Components.jpg
https://sites.google.com/site/cellycompany/contact-us/cytoskeleton