Question

Read the following statements carefully and select the correct ones.
(i) Cardiac fibres are branched with multiple nuclei
(ii) Smooth muscles are unbranched and cylindrical
(iii) Skeletal muscles can be branched or unbranched
(iv) Smooth muscles are non-striated

• A. Only (iv)
• B. (ii) and (iii)
• C. (iii) and (iv)
• D. Only (iii)

Answer 1

The correct option is A Only (iv)

Muscle is a soft tissue comprising of protein filaments - actin and myosin that slide one another producing contraction and changes in both the length and the shape of the cell. It helps in movement of body. There are 3 types of muscles:

• The smooth muscle fibres taper at both ends (fusiform) and do not show striations (non-striated). Smooth muscles are spindle-shaped, uninucleate, unbranched, and involuntary.
• Cardiac muscle fibres are uni-nucleate, with only one nucleus per fibre, and they can sometimes be branched.
• Skeletal muscle has multiple nuclei present in a single cell and unbranched.