GCSE Biology B1 – Cell Biology – AQA – 2023/2024 – Complete Revision Notes

GCSE Biology B1: Cell Biology - AQA Specification


1. Cells
Cell Types
- Eukaryotic cells: Have a nucleus (e.g. animal, plant cells).
- Prokaryotic cells: No nucleus (e.g. bacteria).


Animal Cell Structure
- Nucleus - contains genetic material (DNA).
- Cytoplasm - site of chemical reactions.
- Cell membrane - controls entry/exit of substances.
- Mitochondria - site of aerobic respiration.
- Ribosomes - site of protein synthesis.


Plant Cell Structure (plus animal cell parts)
- Cell wall - strengthens the cell (cellulose).
- Permanent vacuole - contains cell sap.
- Chloroplasts - photosynthesis (contain chlorophyll).


Prokaryotic Cells (Bacteria)
- Cell wall, cell membrane, cytoplasm.
- Single circular DNA strand - free in cytoplasm.
- Plasmids - small DNA loops.


2. Microscopy
Types of Microscopes
- Light microscopes - lower magnification and resolution.
- Electron microscopes - higher magnification/resolution, view internal structures.


Calculations
- Image size = Actual size × Magnification


Microscope Practical (Required)