1. Which muscle cells have the greatest ability to regenerate? a. skeletal smoot
ID: 3523539 • Letter: 1
Question
1. Which muscle cells have the greatest ability to regenerate? a. skeletal smooth e. no muscle can regenerate b. cardiac c. cardiac & skeletal d 2. What is the role of tropomyosin in skeletal muscles? a. Tropomyosin is the name of a contracting unit. b. Tropomyosin serves as a contraction inhibitor by blocking the myosin binding sites on the actin molecules. c. Tropomyosin serves as a contraction inhibitor by blocking the actin binding sites on the myosin molecules. d. Tropomyosin is the receptor for the motor neuron neurotransmitter. 3. The strongest muscle contractions are normally achieved by a increasing stimulus above the threshold b. increasing stimulus above the treppe stimulus c. increasing the stimulation up to the maximal stimulus d. recruiting small and medium muscle fibers 4. Which of the following is required for excitation- contraction coupling? a. Ca2+ only d. ATP and glucose b. Ca2+ and ATP c. ATP only 5. Intramuscular injection are the best method to deliver a large amount of medicine that have to deliver over a long period of time. Is this statement true or false? a. True b. False 6. Which muscle is tightened and shortened in a child with Congenital Muscular Torticollis? a. Scales b. Trapezius c. Splenius capitis d. SternocleidomastoidExplanation / Answer
Ans 1 Among the following the smooth (involuntary) muscles possess the greatest ability to regenerate, as the smooth muscle fibres retain their property to divide unlike the cardiac and skeletal muscles and thus, possess the maximum ability to regenerate.
A) skeletal (voluntary) muscles have lost their ability to divide but they possess the property called as hypertrophy. This property is due to presence of satellite cells beneath the basal lamina of the muscle fibre. Therefore, whenever the skeletal muscle fibres are injured these satellite cells start dividing and tend to fuse with injured muscle fibre helping in repair and regenration.
B) Cardiac mucles have the least possibility to regenrate. Once, injured they die and are irreplacable.
C) this option is incorrect
D) Smooth muscles possess the highest regenrating tendency. The correct answer.
E) incorrect answer
Ans 2 Our muscles are made up of muscle fibres which are in turn made up of structural and functional unit called as Sacromere. The sacromere in turn is made of four protein subunits - actin (thin filament), myosin (thick filament) , troponin and tropomyosin. These all work as one unit to bring about muscular contarction and relaxation. When the muscles contracts the thick and thin filaments slide over each other and this occurs in presence of troponin. However, presence of tropomyosin initiates muscle relaxation as it inhibits the contact between the myosin heads and the actin filaments. Therefore, the correct answer to the question is (b) i.e. it serves as inhibitor by blocking the myosin binding sites on actin filament.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.