ScienceFreePrintable

How Body Parts Work

A free science worksheet ready for your classroom. Open in Kuraplan to grab the print-ready PDF, customize it for your students, or generate a fresh version in seconds.

Download now

Name:Date:

How Body Parts Work

Evie and Jarrah are working at a dinosaur dig. After carrying a heavy equipment case across the site, they notice their breathing and heart rates have increased. Use the information and diagrams below to investigate how body parts work together. Write in complete scientific sentences where asked.

Follow the oxygen

Oxygen enters the body when we breathe in. In the lungs, oxygen moves into tiny blood vessels. The heart pumps oxygen-rich blood through blood vessels to body cells. Cells use oxygen to release energy from nutrients. Carbon dioxide, a waste gas, travels in the blood back to the lungs and is breathed out.

Air breathed in

Lungs: oxygen enters blood

Heart pumps blood

Blood delivers oxygen to cells

1.Choose the correct route for oxygen to reach a leg muscle after it is breathed in.

Lungs → blood → heart → blood vessels → muscle cell
Stomach → heart → lungs → muscle cell
Lungs → kidneys → stomach → muscle cell
Heart → lungs → blood → muscle cell

2.Which two systems work together most directly to move oxygen from the air to body cells?

3.True or false: The heart adds oxygen to the blood; the lungs pump blood around the body.

TrueFalse

Food, movement and control

The digestive system breaks food into small molecules. Most nutrients pass from the small intestine into the blood. The circulatory system delivers these nutrients to cells. The nervous system, including the brain and spinal cord, sends signals that help coordinate movement. Muscles pull on bones to move the body; the skeleton supports the body and protects organs.

4.Match each body part to its main function. Write the correct number beside each letter.

A. Brain
B. Lungs
C. Small intestine
D. Kidneys

2. Coordinates and controls many body activities
4. Absorbs most digested nutrients into the blood
1. Filters wastes from the blood and helps make urine
3. Exchanges oxygen and carbon dioxide

5.Evie eats a sandwich before the next dig. Explain how the digestive and circulatory systems work together to make nutrients available to her cells.

6.Jarrah carries equipment uphill. Explain why his breathing rate and heart rate rise during this activity.

7.The skull protects the brain. Name another body structure that protects an organ, and identify the organ it protects.

8.A spinal cord injury can interrupt signals travelling between the brain and parts of the body. Predict one possible effect and explain the link.

9.Put these events in a sensible order to show how a muscle cell can use energy from food: nutrients enter the blood; food is digested; cells use nutrients and oxygen to release energy; nutrients travel to cells.

10.Choose the best explanation of how body systems cooperate during movement.

The nervous system coordinates signals, muscles pull on bones, and the circulatory and respiratory systems help supply working cells.
The skeleton sends oxygen directly to the brain, while the stomach pumps blood.
The digestive system moves bones, and the kidneys control muscle signals.
Each body system works separately and does not affect the others.

11.In two or three sentences, describe how at least three body systems work together when a person runs.