Myofibrils are Made Primarily Of

Question

Myofibrils are made primarily of
A)actin and myosin.
B)epimysium.
C)ATP and ADP.
D)troponin.
E)tropomyosin.

Accepted Answer

Myofibrils are the contractile units of muscle cells and are made up of actin and myosin proteins. These proteins work together to produce muscle contractions. The other choices (B, C, D, E) are not correct because epimysium is a connective tissue that surrounds the whole muscle, ATP and ADP are energy molecules used by muscles, troponin is a regulatory protein involved in muscle contraction, and tropomyosin is another regulatory protein that helps regulate muscle contractions. However, neither Troponin nor Tropomyosin alone constitutes the majority of Myofibrils, hence ACTIN and MYOSIN together is the Best answer.