Biology A-Level
cohesion
What cohesion means in Biology A-Level, as defined for AQA.
Definition of cohesion
Check what you remember
Read the wording for your board, then hide it and explain cohesion in your own words. Rough notes are fine. This is a self-check, with no mark or grade.
Reference: AQA
Water molecules are polar and form hydrogen bonds with one another, so they stick together and the entire column is pulled up as a single unit.
Topics that use cohesion
- Mass transport in plants (AQA A-Level)
Related terms
- companion cells
- Hydrostatic pressure gradients
- Mass flow hypothesis
- Ringing experiments
- Tracer experiments
- Transpiration
- adhesion to the wall
- sieve tube elements and sieve plates
Using cohesion in the exam
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