Question

Select all correct characterizations of cardiac muscle.

a.under voluntary control
b.cells are long and cylindrical
c.cells have a single, centrally placed nucleus
d.adjacent cells are bound at intercalated disks
e. fibers are striated

Answer 1

The cardiac muscle is characterized by cells with a single nucleus, binding via intercalated discs, and striated fibers. Unlike skeletal muscles, cardiac muscles operate involuntarily and are structured to contract synchronously.

Step-by-step explanation:

The correct characterizations of cardiac muscle include:

• Cells have a single, centrally placed nucleus.
• Adjacent cells are bound at intercalated discs.
• Fibers are striated.

Cardiac muscle is not under voluntary control, so it is involuntary. The cells themselves are branched rather than long and cylindrical like skeletal muscle fibers. The presence of intercalated discs is unique to cardiac muscle, as they facilitate both mechanical and electrical coupling between cells for synchronized contraction of the heart.