Which of the three muscle types is found only in the heart?

• A. Smooth muscle
• B. Skeletal muscle
• C. Connective tissue
• D. Cardiac muscle

Answer: (D)

Verified step by step guidance

1. Begin by identifying the three main types of muscle tissue in the human body: smooth muscle, skeletal muscle, and cardiac muscle.
2. Understand the location and function of each muscle type: Smooth muscle is found in the walls of hollow organs like the intestines and blood vessels, skeletal muscle is attached to bones and is responsible for voluntary movements, and cardiac muscle is found exclusively in the heart.
3. Recognize that cardiac muscle is unique due to its specialized structure and function, which allows it to contract rhythmically and continuously without fatigue, a necessity for maintaining the heartbeat.
4. Note that connective tissue is not a type of muscle but rather a type of tissue that supports, connects, or separates different types of tissues and organs in the body.
5. Conclude that the muscle type found only in the heart is cardiac muscle, distinguishing it from smooth and skeletal muscle based on its exclusive location and function.