Every single cell in your body contains a complete set of instructions for building you. These instructions are called 1, and they're written in a chemical code that's been passed down through your family for generations.
The Body's Instruction Manual
Your genes are stored inside the nucleus of every cell, wound up tightly in structures called chromosomes. Humans have 23 pairs of chromosomes, which means we have about 20,000 different genes in total. Each gene contains the instructions for making a specific protein, and proteins do most of the actual work in your body — from helping you digest food to fighting off infections.
Think of genes like recipes in a massive cookbook. Each recipe (gene) tells your body how to make a particular dish (protein). Some recipes make the proteins that determine your eye colour, others make the proteins that help your muscles grow, and still others make the proteins that keep your heart beating.
Where Do Your Genes Come From?
You inherited half your genes from your mother and half from your father. That's why you might have your mum's nose but your dad's sense of humour — different combinations of genes create the unique person that is you. Some traits, like having brown eyes, are controlled by just one or two genes. Others, like your height, are influenced by hundreds of different genes working together.
Genes Can Change
Most of the time, genes are copied perfectly from one generation to the next. But occasionally, tiny changes called 1 occur in the genetic code. Most mutations don't cause any problems at all, and some can even be helpful. For instance, a mutation thousands of years ago gave some people the ability to digest milk as adults — quite handy if you're a dairy farmer!
Understanding genes has revolutionised medicine. Scientists can now identify genes that cause certain diseases and are working on ways to fix faulty genes. It's rather like being able to spot the typos in those recipe books and correct them before they cause any trouble with the cooking.
Every cell in your body holds a full set of instructions for building you. These instructions are called genes. They are written in a special chemical code. This code has been passed down through your family for a very long time.
The Body's Instruction Manual
Your genes are kept inside the centre of each cell. This centre is called the nucleus. The genes are wrapped up tightly in bundles called chromosomes. Humans have 23 pairs of chromosomes. In total, we have about 20,000 different genes. Each gene holds instructions for making a specific protein. Proteins do most of the real jobs in your body. They help you digest food and fight off illnesses.
Think of genes like recipes in a giant cookbook from your school library. Each recipe tells your body how to make one dish. The dish is a protein. Some recipes make proteins that decide your eye colour. Others make proteins that help your muscles grow bigger and stronger. Some make proteins that keep your heart beating every single day.
Where Do Your Genes Come From?
You got half your genes from your mum and half from your dad. That is why you might look like your mum but act like your dad. Different mixes of genes make you the unique person you are. Some things, like having brown eyes, are controlled by just one or two genes. Other things, like how tall you grow, are controlled by hundreds of genes all working together.
Genes Can Change
Most of the time, genes are copied perfectly from parent to child. But sometimes, tiny changes happen in the code. These changes are called mutations. Most mutations do not cause any problems at all. Some mutations can even be helpful. Thousands of years ago, a mutation let some people drink milk as grown-ups. That was very useful if your family kept cows and made dairy food!
Learning about genes has changed medicine in a huge way. Scientists can now spot genes that cause certain illnesses. They are working on ways to fix genes that are not working properly. It is a bit like finding spelling mistakes in those recipe books. If you can spot the mistake and correct it, the recipe will turn out just right.