Muscles: How You Move (Part 4)

What You'll Learn

Muscles work in pairs to move bones. When one muscle contracts (gets shorter), the opposite muscle relaxes (gets longer). The biceps and triceps are an example of this pairing.

Key Words

digestive system
respiratory system

Steps

Step 1 — Read

Read the introduction and identify the main idea of this lesson.

Step 2 — Do

Map your pulse: measure your heart rate at rest, after 1 minute of walking, and after 1 minute of jumping. Create a bar graph and explain the differences.

Step 3 — Observe

Observe what happens and describe it in detail.

Step 4 — Record

Record your observations in your science journal with measurements and descriptions.

Check Your Understanding

Question 1

1 of 3

What connects muscles to bones?