Question

Basic Unit of muscle Contraction is?
a) Actin
b) Myosin
c) Sarcomere
d) Tropomyosin

Answer 1

Hint: As we know that, a lack of oxygen in muscles leads to cramps, fatigue sometimes swelling as the body sometimes lacks enough energy to workout. This happens due to lactic acid accumulation in muscles from the metabolism of carbohydrate in the cells. Also, various factors are there beside the lactic acid cause like cramps can also occur due to dehydration as well.

Complete answer:
Option A) Actin- actin is a familiar protein we all know about.
It is a family of globular multi-functional proteins that form microfilaments in the cytoskeleton and the thin filaments in muscle fibrils. It is found in mostly eukaryotic cells. Actin possesses important functions like- muscle contraction, cell motility, cell division and cytokinesis, vesicle and organelle movement.
So, option A is not correct.
Option B) Myosin- myosin is another type of muscle protein other than actin. The main difference between both the muscle protein is it produces dense contractile filaments within muscle cells. It binds actin and hydrolyze ATP and it also transfers force.
So, option B is incorrect.
Option C) Sarcomere- it is a unit of striated muscle tissue. It is a repeating unit of two Z lines. It is the basic unit of muscle contraction. Each sarcomere is composed of two main protein filaments actin and myosin which are the active structures responsible for muscle contraction.
So, option C is correct.
Option D) Tropomyosin- Tropomyosin is a component of actin filaments that plays a vital role in controlling actin filament function in both muscle and nonmuscle cells. These proteins are shaped in coiled form with hetero dimers and homo dimers which lie along alpha helical groove of most actin filaments.
So, option D is not correct.

So, Option B is the correct answer.

Note:
A muscle cramp is a quick and involuntary spasm of any muscle that does not relax. The sudden tightness and intense pain caused by a muscle locked in spasm. Cramps mostly affect the skeletal muscle. If the cramps are severe, it may be sore for days. In the presence of oxygen, pyruvate is broken down in mitochondria, resulting in the creation of acid. This also results as due to overdue of energy the body starts anaerobic glycolysis.