--- title: Staying healthy: germs, vaccines, sleep, food and exercise — a lesson of Mova's school · trees and pragmatics description: «Staying healthy: germs, vaccines, sleep, food and exercise», a lesson of the biology course of Mova's primary school, sentence by sentence with dependency trees and pragmatics. It begins: Your body is a castle under siege by germs too small to see, and it has walls (skin), guards (the immune system --- [Mova](https://md.mova.elamur.ai/free/en/) · [this page in HTML](https://mova.elamur.ai/free/en/corpora/school/biology/72-staying-healthy/) [home](https://md.mova.elamur.ai/free/en/) / [corpora](https://md.mova.elamur.ai/free/en/corpora/) / [school](https://md.mova.elamur.ai/free/en/corpora/school/) / [Biology](https://md.mova.elamur.ai/free/en/corpora/school/biology/) / Staying healthy: germs, vaccines, slee… # Staying healthy: germs, vaccines, sleep, food and exercise Lesson 72 of the biology course of Mova's primary school: 16 sentences, each with its syntax tree and pragmatics. The lessons are written for Mova, and their agreed trees are part of Mova corpus 0.4 (CC BY-SA 4.0). How Mova does on its tests: [the lesson at school](https://md.mova.elamur.ai/free/en/school-run/biology/72-staying-healthy/). - [0](https://md.mova.elamur.ai/free/en/corpora/school/biology/72-staying-healthy/0/) — Your body is a castle under siege by germs too small to see, and it has walls (skin), guards (the immune system), repair teams (platelets) and a thermostat it can turn up to fight back. - [1](https://md.mova.elamur.ai/free/en/corpora/school/biology/72-staying-healthy/1/) — Singing Happy Birthday twice while you wash with soap is not a silly rule: it gives the soap about 20 seconds to grab the grease where germs hide and let the water rinse them away. - [2](https://md.mova.elamur.ai/free/en/corpora/school/biology/72-staying-healthy/2/) — A vaccine is a wanted poster for a germ: the immune system studies a harmless copy, remembers it, and destroys the real germ fast if it ever turns up. - [3](https://md.mova.elamur.ai/free/en/corpora/school/biology/72-staying-healthy/3/) — Cartoons show germs as green monsters you can see, cold weather giving you a cold, and every pill curing everything; in real life colds come from viruses, antibiotics only kill bacteria, and plain soap, sleep, food and play do most of the work. - [4](https://md.mova.elamur.ai/free/en/corpora/school/biology/72-staying-healthy/4/) — Soap grabs grease and dirt where germs hide so water can rinse them off, and it breaks the fatty coat of some viruses; in the 1840s Ignaz Semmelweis saved many mothers' lives by making doctors wash their hands. - [5](https://md.mova.elamur.ai/free/en/corpora/school/biology/72-staying-healthy/5/) — A sneeze shoots droplets that can travel a few metres, and sneezing into the elbow keeps germs off the hands that touch pencils, door handles and friends. - [6](https://md.mova.elamur.ai/free/en/corpora/school/biology/72-staying-healthy/6/) — A vaccine shows the immune system a harmless copy or piece of a germ, and memory cells then destroy the real germ fast; Edward Jenner made the first vaccine with cowpox in 1796, and vaccines helped wipe out smallpox by 1980. - [7](https://md.mova.elamur.ai/free/en/corpora/school/biology/72-staying-healthy/7/) — Colds are caused by viruses, most often rhinoviruses; antibiotics do nothing against viruses, and going out with wet hair does not give you a cold. - [8](https://md.mova.elamur.ai/free/en/corpora/school/biology/72-staying-healthy/8/) — When you graze your knee, platelets plug the wound and threads of fibrin make a net that dries into a scab, a natural plaster under which new skin grows; picking it can let germs in and leave a scar. - [9](https://md.mova.elamur.ai/free/en/corpora/school/biology/72-staying-healthy/9/) — Normal body temperature is about 37 degrees Celsius; in a fever the brain turns the thermostat up to make life harder for germs, and shivering is the body heating itself to the new setting. - [10](https://md.mova.elamur.ai/free/en/corpora/school/biology/72-staying-healthy/10/) — No single food has everything the body needs, so a balanced meal gives protein for building, carbohydrates for energy, some fat, vitamins, minerals and fibre; sailors once got scurvy from lack of vitamin C until lemons and limes were added to their food. - [11](https://md.mova.elamur.ai/free/en/corpora/school/biology/72-staying-healthy/11/) — Bacteria in plaque eat sugar and make acid that dissolves enamel into cavities; brushing twice a day for two minutes with fluoride toothpaste helps, and brushing at bedtime matters most because bacteria feed on sugar left in the mouth all night, and enamel, the hardest substance in the body, cannot grow back. - [12](https://md.mova.elamur.ai/free/en/corpora/school/biology/72-staying-healthy/12/) — Exercise makes the heart pump faster and the lungs breathe harder; the heart gets stronger with use, running and jumping make bones stronger, and children should be active for about an hour a day on average. - [13](https://md.mova.elamur.ai/free/en/corpora/school/biology/72-staying-healthy/13/) — The body is about 60 percent water; sweat cools the skin as it dries, and pale yellow wee is a simple sign you are drinking enough. - [14](https://md.mova.elamur.ai/free/en/corpora/school/biology/72-staying-healthy/14/) — Ultraviolet rays in sunlight damage skin cells and cause sunburn; sunscreen blocks much of it but must be put on again after swimming, and you can burn on a cloudy day, because most ultraviolet rays pass through thin cloud. - [15](https://md.mova.elamur.ai/free/en/corpora/school/biology/72-staying-healthy/15/) — In 1928 Alexander Fleming noticed that a mould, Penicillium, had killed bacteria on a dish, which led to penicillin; antibiotics only work on bacteria, and taking them when not needed helps bacteria become resistant. - ← previous: [Growing: teeth, height, hair, nails, from baby to grown-up](https://md.mova.elamur.ai/free/en/corpora/school/biology/71-growing-from-baby-to-grown-up/) - next →: [Evolution simply: why living things change over many generations](https://md.mova.elamur.ai/free/en/corpora/school/biology/73-evolution-simply/) - ↑ back to [Biology](https://md.mova.elamur.ai/free/en/corpora/school/biology/)