Question

Write the difference between Actin and Myosin.

Answer 1

Hint:The sarcomere is the essential contractile muscle fibre unit. A sarcomere consists of two main protein filaments called actin and myosin which are the active structures responsible for muscle contraction.

Complete answer:
The muscles are composed of proteins. Myosin and actin are two molecules of protein that are found in muscles and primarily involved in muscle contraction in both animals and humans. Both actin and myosin operate by regulating voluntary muscle movements within the body, along with regulatory proteins such as troponin, meromyosin, and tropomyosin. Actin and myosin proteins make filaments that are arranged in the myofibrils in a longitudinal way. They are also responsible for both cellular and non-cellular motions.
The difference between actin and myosin are given below.

Actin	Myosin
Actin is a category of globular proteins that are the most common proteins in most of the eukaryotic cells that help to give the body shape, form, and mobility.	Myosin is also called motor proteins that, along with actin proteins, form the basis for muscle fibre contraction.
Actin proteins are present in both the A and I bands of sarcomere.	Myosin proteins are present only in the sarcomere A bands.
These are thinner and shorter in size.	These are thicker and longer in size.
Its filaments are more abundant than myosin	Its filaments are less abundant than actin.
The surface of the action is smooth.	The surface of the myosin is rough.
It is located in the cell wall, cell membrane, muscle fibres, and microfilaments.	It is located in muscle cells.

Note:The key difference between actin and myosin is that actin is a protein that produces small, contractile filaments within muscle cells, while myosin is a protein that produces thick, contractile filaments within muscle cells.