[Campbell Biology P.928] Which of the following statements correctly differentiates between ... | Practice Question

Which of the following statements correctly differentiates between the three types of muscle tissue found in vertebrates skeletal, smooth, and cardiac ?

  • A: Skeletal muscle is responsible for involuntary movements, while smooth muscle and cardiac muscle are responsible for voluntary movements.
  • B: Cardiac muscle lacks striations and is found in the walls of internal organs, similar to smooth muscle.
  • C: Skeletal muscle fibers are branched and interconnected by intercalated disks, unlike cardiac muscle.
  • D: Smooth muscle lacks striations and is spindle-shaped, while both skeletal and cardiac muscles are striated.

Explanation

Skeletal and cardiac muscles are both striated, meaning they have a striped appearance due to the arrangement of contractile units. Smooth muscle, however, lacks these striations and its cells are spindle-shaped. Skeletal muscle is voluntary, while smooth and cardiac muscles are involuntary. Cardiac muscle has branched fibers and intercalated disks, features not found in skeletal muscle.