Question

1. what are the main functions of the muscular system mentioned in the passage?

a. digestion, breathing, blood circulation, and sensory perception
b. movement, maintaining posture, stabilizing joints, and generating heat
c. hearing, vision, smell, and taste
d. thinking, memory, emotion, and speech

1. how do skeletal muscles help you move your body?

a. by contracting and relaxing in pairs
b. by stretching and shrinking
c. by pushing and pulling
d. by vibrating and shaking

1. what role do smooth muscles play in the digestive system?

a. they help you breathe.
b. they help move food through your body.
c. they help you stand up straight.
d. they help pump blood.

Explanation:

1. The muscular system's main functions are movement, maintaining posture, stabilizing joints, and generating heat. Digestive, sensory, and cognitive - related functions are not primary muscular system functions.
2. Skeletal muscles work in pairs by contracting and relaxing to move the body. Stretching - shrinking, pushing - pulling, and vibrating - shaking are not the main mechanisms.
3. Smooth muscles in the digestive system help move food through the body via peristalsis. Breathing is related to respiratory muscles, standing straight is related to skeletal muscles, and pumping blood is the heart's (cardiac muscle) function.

Answer:

1. B. movement, maintaining posture, stabilizing joints, and generating heat
2. A. by contracting and relaxing in pairs
3. B. They help move food through your body.