Human organs
This Topic is About...
- I will find out where the important organs are in the human body.
- I will find out what body organs do.
- I will look at results recorded on a bar chart and look for patterns.
- I will make predictions and see if they are right.
- I will collect observations in a table.
You’re going to be a science explorer!
Key Words
- beat
- brain
- exercise
- lungs
- organ
- blood
- breath
- heart rate
- muscle
- pulse
- blood vessels
- breathe
- intestines
- nutrients
- stomach
Tap to Learn the Meanings!
- beat: The rhythmic movement of the heart.
- brain: The organ that controls thoughts, feelings, and actions.
- exercise: Physical activity that helps keep the body healthy.
- lungs: The organs that take in oxygen when we breathe.
- organ: A part of the body that has a special job, like the heart or liver.
- blood: The red liquid that carries oxygen and nutrients through the body.
- breath: The air we take in and release when we breathe.
- heart rate: How many times the heart beats in one minute.
- muscle: Tissue in the body that helps us move.
- pulse: The beat of the heart that can be felt in blood vessels.
- blood vessels: Tubes that carry blood around the body.
- breathe: To take air in and out of the lungs.
- intestines: Long tubes that help digest food and absorb nutrients.
- nutrients: Substances in food that help the body grow and stay healthy.
- stomach: The organ where food begins to break down after eating.
Fantastic! You’re learning key words about how the human body works.
Your brain
Like your heart, your brain never stops working. Your brain gets messages from your sense organs, your eyes, ears, tongue, skin and nose. Your brain uses that information when you think, talk, write and move. This helps you talk, write, do mathematics, play games and more. You need your brain for everything you do!
If you make your brain work hard it gets better. Scientists know that, even when you get things wrong, if you keep trying your brain will improve.
FUN QUESTIONS
1. Can you feel your heart beating?
Show answer
2. Have you felt your heart beat faster after you have been running or playing?
Show answer
Exercise and heart rate
You will need: a stopwatch
Marcus and Zara are investigating how their hearts speed up when they exercise.
Observation: Your heart rate went up from 65 beats per minute to 85 beats per minute.
Zara’s heart rate at different times
The bar chart shows how Zara’s heart rate changed when she exercised and then rested. The data are summarised in this table:
| Time we measured heart rate | Heart rate (beats per minute) |
|---|---|
| At rest | 65 |
| After 1 minute of exercise | 85 |
| 2 minutes after the exercise | 65 |
Questions about the bar chart
Answer these questions.
- What was Zara’s heart rate before the exercise?
- What was Zara’s heart rate after exercise?
- What was Zara’s heart rate after two minutes of rest?
- The bar chart shows a pattern. Do you think the same pattern always happens when you exercise and then stop?
Try it yourself
Now use a watch to take the pulse of a friend at rest, after 1 minute’s exercise and again two minutes later.
Do you see a similar pattern of an increase in heart rate followed by a return to the resting heart rate?
Your lungs
In your chest are your two lungs. When you breathe in, your chest gets bigger and sucks air into your lungs. Oxygen in the air then moves into your blood.
If you exercise your body will need more oxygen. Your lungs will take more breaths each minute so that there is more oxygen in your blood. Children take more breaths than an adult because their lungs are smaller.
How many breaths in one minute?
You will need: a stopwatch
Predict how many breaths you will take in one minute. Predict the number at rest and then predict the number after exercise.
While you sit at rest, count the times you breathe in during one minute. This is your breathing rate at rest.
Then after one minute of gentle exercise, count your breaths again for one minute. This is your breathing rate after exercise.
Example observations:
✔ “That’s 26 breaths in one minute.”
✔ “I predict it may be about 35 breaths in one minute.”
✔ “After one minute of exercise I will count how many times I breathe in for one minute.”
Record your results
| My prediction of breaths in one minute at rest | My prediction of breaths in one minute after exercise | Number of breaths in one minute at rest | Number of breaths in one minute after exercise |
|---|---|---|---|
Were your predictions right?
Investigating breathing rates
Sofia and Marcus tested the breaths per minute of two teachers. They recorded the results in this table.
| Person | Age | Prediction At rest | Breathing Rate at Rest | Prediction after exercise | Breathing Rate after Exercise |
|---|---|---|---|---|---|
| Sofia | 11 | 20 | 26 | 40 | 50 |
| Marcus | 11 | 35 | 27 | 45 | 48 |
| Mr. Zan | 31 | 30 | 23 | 40 | 41 |
| Mrs. Bell | 29 | 25 | 24 | 35 | 39 |
FUN QUESTIONS
1. Why does the breathing rate per minute always increase after exercise?
Show answer
2. Whose breathing rate per minute increased most?
Show answer
3. Why was the breathing rate per minute of the adults lower than that of the children?
Show answer
Your stomach and intestines
When you eat, your food goes to your stomach and intestines. Your intestines absorb important nutrients from your food. Nutrients are things in your food that help your body to grow and work well. Nutrients help to keep you healthy.
The food then passes out of your intestines and into the toilet as waste.
FUN QUESTION
4. What organ makes the blood travel around your body?
Show answer
Your brain
Like your heart, your brain never stops working. Your brain gets messages from your sense organs, your eyes, ears, tongue, skin and nose. Your brain uses that information when you think, talk, write and move. This helps you talk, write, do mathematics, play games and more. You need your brain for everything you do!
If you make your brain work hard it gets better. Scientists know that, even when you get things wrong, if you keep trying your brain will improve.
FUN QUESTIONS
5. Can you remember a time when you had to think very hard?
Show answer
6. Do you know a game that makes your brain work hard?
