I am not a biologist. In fact, at school I didn't really enjoy science, especially Chemistry, and I didn't find my love for human biology until I was in my late teens! However, Megan, aged 11 (KS3), clearly has a passion for science and has put together some amazing facts for us below.
3 Facts About the Human Body! 😊
Millions of people take a mind-altering drug every day without even realising it! Caffeine is a naturally occurring drug that has a stimulant effect on our brains. Caffeine is found in many everyday products, including coffee, tea most cola and energy drinks, chocolate, and painkillers.
If you consume caffeine it passes through your stomach lining and into your bloodstream. The blood will then flow to your brain, where a chemical reaction takes place that speeds up the messages between your body and brain, making you feel more alert.
This doesn’t sound bad, but there are some downsides. If you’re used to a daily dose of caffeine, then you might feel unwell if you stop having it. These effects are called withdrawal symptoms, and can include irritability, headache, and a lack of concentration.
You grow a new liver every single year!
Your body is made up of cells that are constantly dying. But don’t worry, these cells can also regenerate, which means new cells grow in their place. Here’s how long some cells in different parts of the body last before being renewed:
Stomach lining: 5 days
Taste buds: 10 days
Skin: 3 weeks
Red blood cells: 4 months
Nails: 6-10 months
Eye lens: Your eye lens never replace themselves; they are as old as you are!
Humans can hold their breath for as long as 20 minutes! Most adults can only hold their breath for 30 seconds - 1 minute. But free divers (swimmers who go underwater without a snorkel or diving equipment) can train their bodies to last 20 times longer. Before a dive, free divers relax their bodies, which reduces how much oxygen they need and slows their heartbeat. Free divers also learn how to resist a powerful urge to take in oxygen and breathe out carbon dioxide.
These facts about the human body are pretty incredible, and I want to thank Megan for teaching me more about the amazing machine we all inhabit.