Which statement about smooth muscle cells is true?
A) They are spindle-shaped and multinucleate.
B) Their plasma membrane is insensitive to stretching.
C) Some occur in sheets and are electrically coupled through gap junctions.
D) Their arrangement of actin and myosin filaments is more regular than that found in skeletal and cardiac muscle cells.
E) They occur more extensively in the walls of veins and capillaries than arteries because of the difficulty associated with returning blood to the heart against gravitational forces.

Question

Quizplus · Accepted Answer

Smooth muscle cells can occur in sheets or layers and are electrically coupled via gap junctions, allowing them to contract in a coordinated manner.

Answer: D
 The arrangement of actin and myosin filaments in smooth muscle cells is more irregular compared to skeletal and cardiac muscle cells. This allows for greater flexibility and adaptability in contraction.

Answer: E
 Smooth muscle cells are found more extensively in the walls of veins and other blood vessels than arteries because these vessels experience less pressure and flow, making it more difficult to return blood to the heart. Smooth muscle cells help facilitate this process by contracting and relaxing to move blood back towards the heart.

Which Statement About Smooth Muscle Cells Is True