Instant Access to A Level Biology Revision

Sign up now to get access to the entire library of A Level Biology resources for all exam boards

Join now

If you're ready to pass your AQA A-Level Biology exams, become a member now to get complete access to our entire library of revision materials.

Join over 22,000 learners who have passed their exams thanks to us!

Join now →

Or try a sample...

Not ready to purchase the revision kit yet? No problem. If you want to see what we offer before purchasing, we have a free membership with sample revision materials.

Signup as a free member below and you'll be brought back to this page to try the sample materials before you buy.

Download the samples →

3.2 Cells

  • All life on Earth exists as cells. These have basic features in common. Differences between cells are due to the addition of extra features. This provides indirect evidence for evolution.
  • All cells arise from other cells, by binary fission in prokaryotic cells and by mitosis and meiosis in eukaryotic cells.
  • All cells have a cell-surface membrane and, in addition, eukaryotic cells have internal membranes.
  • The basic structure of these plasma membranes is the same and enables control of the passage of substances across exchange surfaces by passive or active transport.
  • Cell-surface membranes contain embedded proteins. Some of these are involved in cell signalling – communication between cells. Others act as antigens, allowing recognition of ‘self’ and ‘foreign’ cells by the immune system. Interactions between different types of cell are involved in disease, recovery from disease and prevention of symptoms occurring at a later date if exposed to the same antigen, or antigen-bearing pathogen.

Source: AQA Spec

Included in this download

3.2.1Cell structure
3.2.2All cells arise from other cells
3.2.3Transport across cell membranes
3.2.4Cell recognition and the immune system