Question

What is the location of troponin in the process of muscle contraction?
A. Attached to myosin filament
B. Attached to tropomyosin
C. Attached to myosin cross bridge
D. Attached to T - tubule

Answer 1

The process of muscle contraction occurs by calcium ions getting attached to troponin which is placed between actin filament and is also attached to a muscle protein.

Step by step answer: Soft tissue is found in most animals and this soft tissue is called muscle. A muscle fiber is made up of muscle proteins actin and myosin which slide over each other for the process of contraction. Both the length and shape of the cell is changed during the process of contraction. -Microfilaments are made up of actin which belongs to the family of a globular multifunctional protein. It plays an important role during the process of muscle contraction. Myosin belongs to the superfamily of motor proteins and is dependent on ATP and responsible for actin-based motility.
-Troponin complex or troponin is composed of three regulatory proteins which is important during the process of muscle contraction. It lies within the groove between actin filaments and is attached to the tropomyosin protein during the muscle contraction process.
-Tropomyosin blocks the attachment site for the myosin cross-bridge and prevents contraction in a relaxed state of the muscle. Muscle cells are stimulated by action potential causing calcium channels to open in the sarcoplasmic membrane and release calcium in the sarcoplasm.
-The released calcium gets attached to troponin causing it to change the shape of the muscle.
So, option B is the correct answer.

Note: Some of the subtypes of troponin are sensitive and acts as an indicator of damage to the heart muscle. Cardiac troponin acts as a marker of all heart damage. Elevated levels of troponin are used in the diagnosis of many conditions.