Primary Science – Circulatory and Respiratory Systems
Explain Your Answer Clearly
This science revision note aims to help your child:
– remember the scientific keywords needed to explain why a heartbeat is faster.
– take note of the importance of respiration
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MUST-KNOW about circulatory and respiratory systems:
When the rate of activity increase, the amount of energy needed by the body increase and this causes:
- Heart rate to increase.The heart pumps faster to transport blood containing digested food and oxygen to the body cells which is used for respiration to release more energy.
- Breathing rate to increase. More oxygen is taken in for respiration to release more energy and more carbon dioxide is transported to the lungs for removal.
Take note:
You have to state and explain the process (respiration) that takes place.
Question
The table below shows the heart rate for John when he is reading.
State and explain how John’s heart rate would change if he were running.
STEP 1
Compare the energy level between the activities. Relate this to the breathing rate and heart rate.
Step 2
Explain the purpose of why the heartbeat rate changes.
Remember to compare by using comparative words.
Link to the heartbeat rate.
FINALLY, piece your answer together.
State and explain how John’s heart rate would change if he were running.
Answer
When John is running, his heart rate and breathing rate will increase. Running requires more energy than reading. His heart will pump faster to transport digested food and oxygen to the body cells which is used to increase the rate of respiration to release more energy. Carbon dioxide is transported to the lungs for faster removal.
Additional learning material for this topic
Do read another question on circulatory and respiratory systems here >>> https://scienceshifu.com/p5-science-circulatory-and-respiratory-system-activity-level/
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