Cell Structure Basics

Cells are the fundamental units that make every living organism tick. Think of them as microscopic factories surrounded by a cell surface membrane, packed with genetic material (DNA) and filled with a jelly-like substance called cytoplasm containing specialised structures called organelles.

There are two main types of cells you need to know about. Eukaryotes (meaning "true nucleus") are the fancy cells found in plants, animals, and fungi - they've got a proper nucleus and loads of membrane-bound organelles. Prokaryotes are the simpler cells found in bacteria, with no nucleus and their DNA just floating about freely.

The nucleus is basically the cell's control centre, containing all the DNA that runs the show. It's surrounded by a double membrane called the nuclear envelope. Inside, you'll find chromatin (loosely packed DNA and proteins) and the nucleolus, which has the important job of making ribosomes.

Animal cells contain brilliant organelles like mitochondria (the powerhouses that carry out aerobic respiration), whilst plant cells have extra features like chloroplasts for photosynthesis, a large central vacuole for storage, and a tough cell wall for protection. Plant cells also have plasmodesmata - tiny pores that let neighbouring cells communicate with each other.

Quick Tip: Remember that plant cells have everything animal cells have, plus three extras: cell wall, chloroplasts, and a large permanent vacuole!