Diseases
🌟 This Topic is About...
- 🦠 I will find out about the types of living things that cause diseases.
- 📚 I will learn how to find information about different diseases.
- 🛡️ I will discover how our body protects us from infectious diseases.
- 🤝 I will explore ways to stop diseases from spreading.
- 🧩 I will group and compare methods that prevent diseases.
- 📊 I will draw a dot plot to show my results.
- 🦟 I will learn how to avoid being bitten by insects.
Let’s learn how to stay healthy and stop germs from spreading! 💪🌿
🌟 Key Words
- barrier
- host
- mucus
- repellent
- defence
- hygiene
- parasite
- vector
📖 Tap to Learn the Meanings!
- 🧱 barrier: Something that blocks germs or stops them from entering the body.
- 🧍 host: A living thing that another organism (like a germ or parasite) lives on or inside.
- 💧 mucus: A sticky liquid made by your body that traps dust and germs in your nose and throat.
- 🦟 repellent: A spray or cream that keeps insects away.
- 🛡️ defence: The ways your body protects itself from diseases.
- 🧼 hygiene: Keeping clean to stay healthy and stop germs from spreading.
- 🦠 parasite: A living thing that survives by taking food from another living thing.
- 🚶 vector: An animal (like a mosquito) that carries and spreads disease germs.
You’re getting great at learning science words! 🎉
🧫 What Causes Disease?
Diseases stop our bodies from working properly. There are different kinds of living things that cause disease. They infect other living things and grow and reproduce on or in the body of the living thing that they infect. Any living thing that lives on or in the body of another living thing is called a parasite. The living thing that a parasite infects is called the host.
🦠 Bacteria
Bacteria are very small living things that we can only see using a microscope. Bacteria cause diseases such as cholera and pneumonia. Not all bacteria are harmful — some are even useful to humans!
🧬 Viruses
Viruses are even smaller than bacteria. All viruses are harmful and can cause diseases in humans, animals, and plants. Some viruses even infect bacteria! Humans get flu, chickenpox, and measles from viruses.
🍄 Fungi
The yeast that we use to make bread rise is a fungus. Mushrooms that we eat are also fungi. But some fungi are parasites that cause diseases. Ringworm in humans and animals, athlete’s foot in humans, and rusts in plants are caused by fungi.
🪱 Other Parasites
There are also other kinds of parasites that cause infectious diseases. Malaria and dysentery are two examples of diseases caused by these parasites.
🤔 FUN QUESTIONS
1a. What is a parasite?
🌟 Show me!
1b. Why are viruses and some bacteria and fungi parasites?
🌟 Show me!
2. Make a table of the different kinds of living things that cause diseases and name two examples of a disease that each one causes.
🌟 Show me!
| Type of Microorganism | Examples of Diseases |
|---|---|
| Bacteria | Cholera, Pneumonia |
| Virus | Flu, Measles |
| Fungus | Ringworm, Athlete’s foot |
| Parasite | Malaria, Dysentery |
Well done! You now know how different microbes cause different diseases. 👏
🛡️ The Body’s Defences
Our body has many ways to stop us from being infected by diseases. These ways are called the body’s defences against diseases.
😢 Tears Help Protect
Tears contain a special chemical that can kill some bacteria, helping to keep our eyes clean and safe.
🤧 Sticky Mucus Traps Germs
Sticky mucus in our noses, windpipe, and other air passages traps germs so they don’t reach our lungs.
🧱 Skin is a Barrier
The skin acts like a strong barrier that stops most germs from getting inside the body.
🧪 Stomach Acid Kills Germs
Acid in the stomach kills many germs that may be on food we have eaten.
🧼 Controlling the Spread of Diseases
Diseases can be spread by body contact and in food, in water and in the air. There are different ways we can help to control the spread of diseases.
🧴 Good Hygiene
Many diseases are spread in food, water and body fluids. We can help prevent the diseases from spreading by good hygiene. This means keeping yourself and the things around you clean.
🧹 Everyday Actions
These are some of the things we can do:
🔍 Think like a scientist: Analyse hygiene methods that people use
Class 5 did a survey of people in their local community to find out which hygiene methods people used. These are their results.
| Method to prevent infectious diseases | Number of people who use the method |
|---|---|
| wash hands after going to toilet | 10 |
| wash hands before working with food | 5 |
| wash hands after working with food | 4 |
| keep the kitchen, toilet and surroundings clean | 12 |
| cover nose and mouth when coughing or sneezing | 7 |
📝 Your tasks:
- Draw a dot plot of the results.
-
a) Which hygiene method do most people use?b) Which hygiene method do fewest people use?
- Why do you think people should wash their hands with soap and water and not just water?
- Why should people wash their hands before and after working with food?
- Why should we cover our nose and mouth when we cough or sneeze?
- Why do you think it is important to dry our hands well with a clean towel?
💬 How are we doing? Ask your partner:
- Can you draw a dot plot of results?
- Can you explain why we should use the different hygiene methods to prevent diseases spreading?
👀 Show sample answers
- 2a:keep the kitchen, toilet and surroundings clean (12 people).
- 2b:wash hands after working with food (4 people).
- 3: Soap breaks down oil and removes germs more effectively than water alone.
- 4: Before: to avoid adding germs to food. After: to remove germs picked up from food.
- 5: To stop droplets carrying germs from spreading to others.
- 6: Drying removes leftover germs and stops them growing in damp hands.
Great work analyzing real data like a scientist! 🌟
🐜 Preventing Insect Bites
Some serious diseases, such as malaria, yellow fever, and sleeping sickness, are spread by insects. Malaria and yellow fever are spread by mosquitoes, while sleeping sickness is spread by the tsetse fly. The insects do not cause the disease, but they spread the disease parasite when they bite. The insects themselves do not get the disease — we call such insects vectors.
🛏️ Ways to Prevent Insect Bites
The best way to prevent diseases spread by insects is to avoid being bitten. Here are some helpful ways to stay safe:
- Sleep under bed nets.
- Wear long sleeves and long trousers.
- Keep doors and windows closed at night when mosquitoes are active.
- Use insect repellents on your skin to keep insects away.
- Burn mosquito coils to keep insects away.