The Basics of Cells
Cells are the basic units of life that make up every living organism. According to cell theory, all living things are made of cells, cells are the fundamental units of structure and function, and all cells come from other cells. There are two main types of cells: prokaryotic cells (simple cells without a nucleus) and eukaryotic cells (complex cells with a nucleus and specialized parts).
Your body's cells have specialized structures called organelles that perform specific jobs. The nucleus acts like the cell's brain, containing DNA and controlling all cellular activities. Surrounding each cell is the cell membrane, a flexible barrier that decides what gets in and out of the cell. Inside the cell is a jelly-like fluid called cytoplasm where organelles float.
Some key organelles include mitochondria, often called the powerhouse of the cell because they produce energy through cellular respiration. The endoplasmic reticulum (ER) is a network of membranes that makes proteins and lipids, while the Golgi apparatus packages and ships these materials to where they need to go.
Did You Know? Your body contains about 37.2 trillion cells, but they're constantly being replaced. Most of the cells you had as a child aren't the ones you have now!
