B1.1 Technologies that revealed the cell
Example
Assess what the light microscope added to our understanding of cells.
- Microscope: it made a hidden scale of life visible, so structures far too small for any eye could suddenly be seen, compared and mapped, and the cell itself was discovered that way.
Example
Assess what staining added to our understanding of cells.
- Staining: most cell parts are transparent — a stain that clings to particular structures gives them contrast, so parts that were invisible against the background suddenly stand out to be studied.
Remember: Electron microscope: far finer resolution than light allows — the internal structure of organelles, membranes seen in cross-section, machinery light itself is too coarse to separate.
B1.2 Cell biology: benefits and harms
Example
Analyse the benefit and the limitation, and who raises each, for a grown skin graft.
- Skin graft: a burn patient's own cells grown into a sheet, so no donor and no rejection; a surgeon notes the weeks it takes to grow and the cost.
Example
Analyse the benefit and the limitation, and who raises each, for insulin made by engineered cells.
- Insulin: engineered cells make it in vats, so supply no longer depends on animals; a pharmacist notes the price set by a few makers.
Example
Analyse the benefit and the limitation, and who raises each, for drug testing on cultured cells.
- Cultured testing: a drug is tried on cells before people, so fewer harms reach patients; a researcher notes that a dish is not a whole body.
Summary
- Microscopes, stains and electron beams each crossed a barrier of sight.
- Cell technologies bring a benefit and a limitation, and different people weigh them.