Cell Biology

Cell Biology is the starting point of GCSE Biology and underpins everything that follows. It covers prokaryotic and eukaryotic cells, specialised cells, microscopy and magnification, cell division by mitosis, stem cells, and transport across membranes by diffusion, osmosis and active transport.

Learn the cell structures and their functions first, since later units constantly refer back to them. Magnification calculations reward careful unit conversion — millimetres to micrometres is where most marks are lost. Osmosis is the topic students find hardest, because it requires thinking about water moving down its own concentration gradient rather than about the solute. Active transport is worth distinguishing clearly: it moves substances against the gradient and requires energy from respiration. This unit includes required practicals on microscopy and osmosis, both of which are examined directly.