Questions: The Muscular System

Question 1

Why do skeletal muscles work in pairs?

• A. Because the body has a left and right side
• B. Because muscles can only pull, so one pulls the bone one way and the other pulls it back
• C. Because one muscle provides energy and the other provides movement
• D. Because having two muscles makes them twice as strong

Answer: (B)

Muscles can only contract (pull) — they cannot push. So to move a bone in two directions, you need two muscles pulling in opposite directions. The biceps bends the elbow by pulling the forearm up; the triceps straightens it by pulling the forearm down. They take turns contracting and relaxing.

Question 2

Cardiac muscle is a type of voluntary muscle because you can choose to make your heart beat faster.

• T. True
• F. False

Answer: False

Cardiac muscle is involuntary — it contracts automatically without conscious control. While exercise or emotions can increase your heart rate, this happens through automatic nervous system signals and hormones, not through a deliberate decision to speed up your heartbeat. You cannot stop or start your heart by thinking about it.

Question 3

Name the three types of muscle tissue and give one example of where each is found in the body.

Model answer: Skeletal muscle is attached to bones and moves the body (example: biceps in the upper arm). Smooth muscle is found in the walls of organs (example: the stomach or intestines). Cardiac muscle is found only in the heart.

Each type is specialized for its role: skeletal muscle is strong and voluntary for body movement, smooth muscle provides slow, sustained contractions for organ function, and cardiac muscle never tires because it must beat continuously throughout life.