Question

Microfilaments are composed mainly of a protein called

• A. Chitin
• B. Myosin
• C. Tubulin
• D. Actin

Answer 1

The correct option is D

Actin

The correct option D.

Explanation of the correct option:

Option D:

1. Actin, a globular protein, makes up microfilaments. Microfilaments are long, thin, cylindrical rods with an extremely small diameter of 6-7 nm.
2. Microfilaments are cytoplasmic protein filaments that are present in eukaryotic cells.
3. They have been modified to interact with different proteins found inside the cells. Additionally, they carry out cytokinesis, gliding, and other cellular motions.
4. Microfilaments typically have a height of 7 nanometers and are made up of two actin strands.
5. Microfilaments serve a variety of purposes. The most notable of these include cytokinesis, amoeboid movements, cell motility (the capacity for independent movement), changes in cell shape, endo- and exocytosis, cell contractility, and, when necessary, the ability to provide mechanical stability to cells.

Explanations of the incorrect options:

Option A:

1. Chitin can be discovered in the cell walls of fungi.
2. They make up the majority of those cell walls.
3. The same protein is present in the radula of mollusks, the exoskeletons of arthropods, and other places. They have no connection to microfilaments.

Option B:

1. Myosin is a member of the Motor Protein superfamily.
2. They are famous in particular for playing a significant role in muscle contraction. Although they look like they are attached to Myosin, microfilaments are actually made of this kind of protein.

Option C:

1. The protein tubulin is a member of the globular superfamily.
2. They are associated with microtubules, which house the majority of the cytoskeleton.
3. The characteristic of eukaryotic cells is this.

Final answer: Microfilaments are composed mainly of a protein called actin.