How Muscles Move Bones

Question 1

When you reach up to grab a basketball from a low shelf, which statement correctly explains how your biceps and triceps move your forearm?

Accepted Answer

Your biceps shortens to bend the elbow as you lift the ball, and then your triceps shortens to straighten the elbow as you lower the ball back down.

Answer

Only the biceps works; the triceps stays relaxed the whole time.

Answer

Both the biceps and the triceps shorten at the same time to bend the elbow.

Answer

Your triceps shortens to bend the elbow, and your biceps shortens to straighten the elbow.

Question 2

Which sentence correctly tells how a muscle in your arm and the muscle in your heart work?

Accepted Answer

You can choose to move your arm, and your heart beats without you thinking about it.

Answer

Both your arm and heart muscles work without you ever deciding.

Answer

You can choose both to move your arm and when your heart beats.

Answer

Your heart decides when to move your arm, and you choose when it beats.

Question 3

You are sitting quietly reading a book. While you read, three different muscles are working: the heart pumps blood, the muscles in your stomach push food along, and the biceps in your upper arm lift the book. Which two of these muscles work without you having to think about them?

Accepted Answer

The heart and the muscles in your stomach that push food along

Answer

The heart and the biceps in your upper arm

Answer

The biceps in your upper arm and the muscles in your stomach that push food along

Answer

The biceps in your upper arm and the heart

Try three questions

When you reach up to grab a basketball from a low shelf, which statement correctly explains how your biceps and triceps move your forearm?

Which sentence correctly tells how a muscle in your arm and the muscle in your heart work?

You are sitting quietly reading a book. While you read, three different muscles are working: the heart pumps blood, the muscles in your stomach push food along, and the biceps in your upper arm lift the book. Which two of these muscles work without you having to think about them?

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