Cell Structure Basics
Every living organism is built from cells, but not all cells are created equal. Eukaryotic cells make up animals and plants - these are the complex cells with a proper nucleus that houses their DNA. Prokaryotic cells, on the other hand, are much simpler and make up bacteria.
Animal and plant cells share several key components that keep them functioning. The cell membrane acts like a bouncer at a club, controlling what substances can enter and leave the cell. Inside, you'll find the nucleus, which is essentially the cell's control centre containing all the DNA and genetic material.
The cytoplasm is where all the action happens - it's the jelly-like substance where chemical reactions take place. Mitochondria are the cell's power stations, providing energy through aerobic respiration. Meanwhile, ribosomes work as tiny factories, constantly making proteins that the cell needs to survive.
Plant cells have three extra features that animal cells don't possess. The cell wall made of cellulose provides extra support and strength, whilst the permanent vacuole stores cell sap and helps maintain the plant's shape. Most importantly, chloroplasts containing chlorophyll enable photosynthesis to occur.
Quick Tip: Remember that bacteria cells are much simpler - they have a single circular strand of DNA floating freely in the cytoplasm, plus special features like flagella for movement and plasmids containing extra genes.