Question

A component of cytoskeleton is
A. Microtubule
B. Bone
C. Chitin
D. Cartilage

Answer 1

Hint: The cytoskeleton is a network of filaments and tubules that spreads across the cell, through the cytoplasm, which is all of the material inside the cell, except the nucleus. It is present in all cells, although the proteins it contains differ between species.

Complete Answer:
- The cytoskeleton protects the cell, gives it structure, organises and connects the organelles, and plays a part in the transport of molecules, cell division and cell signalling. Both cells have a cytoskeleton, but what the cytoskeleton means to note is usually the cytoskeleton of the eukaryotic cells.
- Complex cells with a nucleus and organelles are eukaryotic cells. Plants, animals, fungi and protists have eukaryotic cells. Prokaryotic cells are less complex, with no actual nucleus or organelles but ribosomes, and are found in single-celled species of bacteria and archaea.
- Eukaryotic cytoskeleton consists of three types of filaments, which are elongated chains of proteins: microfilaments, intermediate filaments, and microtubules. Microfilaments are often referred to as actin filaments because they are mainly made up of protein actin; their structure consists of two strands of actin wound in a spiral. They help in cytokinesis, which is the division of a cytoplasm of a cell when a cytoplasm is created.
- Microtubules are the largest cytoskeletal fibre in the area of 23 nm. They are hollow tubes constructed from alpha and beta tubulin. Microtubules form structures such as flagella, which are "tails" that propel a cell forward. They are also present in structures such as cilia, which are appendices that increase the surface area of the cell and, in some cases, allow the cell to move.

The correct Answer is option (A) Microtubule.

Note: Most microtubules in an animal cell originate from a cell called the centrosome, a microtubule organising centre (MTOC). The centrosome is found near the centre of the cell, and the microtubules radiate outward from it. Microtubules are essential in the formation of spindle apparatus (or mitotic spindle) that separates sister chromatids so that one copy can be sent to each daughter cell during cell division.