Instructions
Read each section carefully and answer the questions. This worksheet will explore the amazing partnership between your heart and your lungs!
Part 1: The Mighty Heart
Use the words from the word bank to fill in the blanks in the paragraph below. Each word is used only once.
The human 1. is a powerful muscle that works like a 2. to move 3. all around your body. This blood carries important things like 4. and nutrients to all of your cells. The heart is divided into four sections called 5. . The two upper chambers are called the 6. , and the two lower, more powerful chambers are the 7. . Blood vessels called 8. carry oxygen-rich blood away from the heart, while 9. carry blood back towards the heart.
Part 2: The Breath of Life
Match the part of the respiratory system on the left with its correct function on the right. Write the correct letter in the blank.
1. _____ Lungs
2. _____ Trachea
3. _____ Diaphragm
4. _____ Alveoli
A. The large muscle below the lungs that contracts and relaxes to make you breathe.
B. Tiny air sacs in the lungs where oxygen moves into the blood.
C. The main organs of the respiratory system where gas exchange happens.
D. The tube that carries air from your throat to your lungs, also known as the windpipe.
Part 3: Working Together
Read each statement below. If the statement is correct, write T for True. If it is incorrect, write F for False.
_____ 1. Your heart pumps oxygen directly into your lungs.
_____ 2. The main job of the respiratory system is to bring oxygen into the body and remove carbon dioxide.
_____ 3. Your heart and lungs stop working when you are asleep.
_____ 4. Blood returning to the heart from the body is low in oxygen.
_____ 5. The circulatory and respiratory systems work together to deliver oxygen to your body's cells.
Part 4: Think About It!
When you run or play a sport, your heart beats faster and you breathe more heavily. Why do you think this happens? Explain how your heart and lungs are working together in this situation.
Answer Key
Part 1: The Mighty Heart
- heart
- pump
- blood
- oxygen
- chambers
- atria
- ventricles
- arteries
- veins
Part 2: The Breath of Life
- C
- D
- A
- B
Part 3: Working Together
- F (False. Your lungs put oxygen into the blood, and your heart pumps the blood.)
- T (True)
- F (False. They work continuously to keep you alive.)
- T (True. It has delivered its oxygen and needs to pick up more from the lungs.)
- T (True)
Part 4: Think About It!
(Sample Answer) When you exercise, your muscles work harder and need more energy. To make this energy, they need more oxygen. Your lungs work harder to breathe in more oxygen, and your heart beats faster to pump the oxygen-rich blood to your muscles more quickly. They also work together to remove the extra carbon dioxide your muscles are making.