This is the directory page for Biology. All content is aimed towards the NSW HSC course, so may not be relevant for your state/territory's syllabus.
Cells make up every form of life on earth. In 1839, Theodor Schwann and Matthias Schleiden designed a set of statements, known as Cell Theory. They are as follows:
Cells, and all forms of life for that matter, are divided into two categories: prokaryotes and eukaryotes.
| Characteristics | Prokaryotes | Eukaryotes |
|---|---|---|
| Naming | Meaning "before nucleus" ('pro' meaning 'before') | Meaning "true nucleus" ('eu' meaning 'true') |
| Organelles | No nucelus. No membrane-bound organelles. Most have a cell wall. | Has a nucelus. Has membrane-bound organelles. Some have a cell wall (plants, fungi, etc) |
| DNA | Found loose in the cytoplasm | Found bundled into chromosones in the nucleus |
| Size | Smaller (0.1-0.5 µm) | Larger (10-100 µm) |
| Examples | Bacteria, Archaea | Plants, Fungi, Animals |