Magic School Bus “Works Out”

Front

What happens when the air hits the purple cells in Mrs. Frizzle’s body? They turn ____________.

Back

Red

Front

Which system is your heart in?

Back

Circulatory

Front

Which system are your muscles in?

Back

Muscular

Front

Without enough oxygen, Mrs. Frizzle’s muscles _________ working.

Back

Stop

Front

Lactic acid is what muscles have to make when they have to work without ______________.

Back

Oxygen

Front

What is the main function of the circulatory system?

Back

To transport blood, oxygen, and nutrients throughout the body.

Front

What is the role of muscles in the body?

Back

To help the body move and maintain posture.

Front

What do we breathe in that is essential for our muscles to work?

Back

Oxygen

Front

What happens to muscles when they do not get enough oxygen?

Back

They produce lactic acid and may stop working.

Front

What is lactic acid?

Back

A substance produced by muscles when they work without enough oxygen.