Keeping Clean and Healthy - First Grade Science
Your body is your personal home for life, and taking good care of it is one of the most important responsibilities you have. Throughout your day, you touch doorknobs, play in the grass, handle toys, and sneeze. Microscopic living organisms called germs—including bacteria and viruses—exist everywhere around us. While many microbes are helpful, some germs can cause illness, fevers, and coughs if they enter our bodies. By practicing healthy hygiene habits every day, you keep germs away and keep your body strong, clean, and energized.
Understanding Germs: The Invisible Invaders
Germs are so tiny that they cannot be seen with your eyes alone; scientists must use high-powered microscopes to observe them.
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| THE WORLD OF GERMS |
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| WHAT ARE GERMS? |
| Tiny microscopic organisms (bacteria and viruses) that can cause |
| colds, sore throats, tummy aches, and infections. |
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| HOW GERMS SPREAD: |
| - Touching unwashed surfaces like handles and shared toys. |
| - Coughing or sneezing droplets into the open air. |
| - Rubbing eyes, nose, or mouth with dirty fingers. |
| - Eating food without washing hands first. |
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How Germs Enter the Body
Germs cannot easily pass through healthy, unbroken skin because skin acts like a waterproof shield. However, germs can slip inside your body through mucous membranes in your eyes, nose, and mouth, or through open cuts and scrapes. That is why keeping your hands away from your face is a powerful health habit!
Hand Washing: Your Best Defense
Washing your hands with soap and warm water is the single most effective way to prevent illness and stop the spread of germs.
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| THE 5-STEP HAND WASHING ROUTINE |
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| STEP 1: WET Turn on warm water and wet your hands. |
| STEP 2: LATHER Apply soap and rub hands to make bubbly foam. |
| STEP 3: SCRUB Scrub palms, backs, between fingers, and nails |
| for a full 20 seconds (hum 'Happy Birthday'). |
| STEP 4: RINSE Rinse under running water until bubbles vanish. |
| STEP 5: DRY Dry completely with a clean towel or air dryer. |
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When to Wash Your Hands
You should wash your hands before eating or preparing food, after using the restroom, after blowing your nose, coughing, or sneezing, after playing outside on the playground, and after touching or petting animals.
Dental Hygiene: Caring for Your Teeth
Your teeth help you chew food, pronounce words clearly, and flash a bright smile. Taking care of your teeth keeps your gums healthy and prevents cavities.
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| CARING FOR YOUR TEETH |
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| BRUSH TWICE DAILY Brush in the morning and before bed at night. |
| TWO MINUTES EACH Brush all sides: front, back, and chewing tops.|
| FLUORIDE TOOTHPASTE Strengthens the hard enamel outer layer. |
| FLOSS EVERY DAY Cleans food particles stuck between teeth. |
| DENTAL VISITS Dentists check teeth and clean them thoroughly.|
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What Causes Cavities?
When you eat, tiny bits of food and sugar stay on your teeth. Bacteria living in your mouth consume these sugars and produce a mild acid. If not brushed away, this acid slowly eats into the hard tooth enamel, creating a small hole called a cavity. Brushing cleans away plaque and keeps teeth strong.
Bathing, Coughing Etiquette, and Sun Safety
Good personal hygiene extends to taking regular baths, covering sneezes, and protecting your skin from the sun.
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| DAILY HEALTH AND SAFETY TIPS |
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| BATHING Take regular baths or showers to wash away sweat|
| and dirt from your skin and hair. |
| VAMPIRE SNEEZE Cough or sneeze into the crook of your elbow, |
| not into your bare hands! |
| FIRST AID Clean cuts with clean water, apply antiseptic, |
| and cover with a sterile bandage. |
| SUN PROTECTION Wear sunscreen, sunglasses, and a wide hat on |
| bright sunny days to prevent sunburn. |
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Chapter Review Exercises
Question 1: What are germs, and how can they make a person sick if they enter the body?
Question 2: Describe the five proper steps for washing your hands thoroughly.
Question 3: How does brushing your teeth with fluoride toothpaste protect against tooth cavities?
Question 4: Why is it much healthier to sneeze into your elbow instead of into your bare hands?
Solutions and Explanations
Solution 1: Germs are microscopic living organisms, such as bacteria and viruses. When they enter the body through the eyes, nose, mouth, or cuts, they multiply and can disrupt normal body functions, causing illnesses like colds, coughs, and fevers.
Solution 2: The five steps are: wet hands with clean warm water, apply soap to create a rich lather, scrub all surfaces (palms, backs of hands, between fingers, and under nails) for 20 seconds, rinse away all soap under running water, and dry hands thoroughly with a clean towel.
Solution 3: Brushing removes sticky plaque and food particles that oral bacteria feed on, preventing bacteria from producing damaging acids. The fluoride in toothpaste strengthens the outer enamel shield of the teeth, making them resistant to acid decay.
Solution 4: Sneezing into your elbow traps airborne droplets without getting them on your hands. If you sneeze into your hands, you will transfer those germs onto doorknobs, pencils, toys, and other people whenever you touch things.