The Tiny Rooms Inside You: Meet the Cell

Here is a surprising fact: your body is made of about 37 trillion tiny living units called cells. That is 37,000,000,000,000 — more than all the stars you can see in the night sky! Cells are so small you need a microscope to see most of them. Every muscle you move, every thought you think, and every breath you take happens because your cells are working. But what is actually inside a cell? Let's find out.

A cell is like a tiny factory. Every part of the factory has a special job. Let's look at the main parts one by one. **The Cell Membrane** This is a thin, flexible layer that wraps around the whole cell. Think of it as the factory's outer wall. It controls what goes in and out — letting in food and oxygen, and pushing out waste. **The Cytoplasm** Inside the cell membrane is a jelly-like liquid called the cytoplasm. It fills the cell and holds all the other parts in place. It is like the factory floor where most of the cell's work happens. **The Nucleus** The nucleus is the control centre of the cell. It contains instructions, written in a chemical code called DNA, that tell the cell what to do and how to grow. Think of it as the factory manager's office. **The Mitochondria** Mitochondria (one of them is called a mitochondrion) are the power stations of the cell. They release energy from food so the cell can do its work. Muscle cells have lots of mitochondria because muscles need a great deal of energy. **The Ribosomes** Ribosomes are tiny structures that build proteins. Proteins are the materials the cell uses to repair itself and carry out chemical jobs. Ribosomes are like the factory's construction crew. **Plant Cells Have Extra Parts** Plant cells have all the parts above, plus two extra ones. The cell wall is a stiff outer layer outside the cell membrane that gives the plant support — like a rigid box around the factory. Chloroplasts are green structures that capture sunlight and use it to make food for the plant. This process is called photosynthesis.