1.6 Nervous System and Hormones
Nervous and hormonal coordination, the eye, neurones, synapses, reflexes, blood glucose, water balance and plant hormones.
How to study for CCEA GCSE Biology
Learn each process as a structure-and-mechanism chain, use data with units, and prepare every prescribed practical from planning through conclusion and evaluation.
Core concepts
Concept 1
Nervous signalling is rapid and targeted through neurones, while hormones travel in blood and usually produce slower, longer-lasting effects.
Exam cue: Trace a response from stimulus detection to the named effector without skipping the coordinating pathway.
Concept 2
Receptors, sensory neurones, the central nervous system, motor neurones and effectors form coordinated response pathways, including reflex arcs.
Exam cue: For the eye, connect a structure to how light is controlled or focused on the retina.
Concept 3
Insulin and ADH adjust internal conditions, while auxin distribution produces differential growth in plant shoots responding to light.
Exam cue: For hormonal control, identify the monitored variable, hormone source, target and resulting change.
Risk pitfalls and guardrails
Describing a reflex as involving no central nervous system rather than no conscious decision.
Guardrail: Do not import an England board, Single Award or Double Award structure, and do not replace a biological mechanism with a vague purpose statement.
Confusing insulin with a hormone that raises blood glucose concentration.
Guardrail: Do not import an England board, Single Award or Double Award structure, and do not replace a biological mechanism with a vague purpose statement.
Saying a shoot bends because auxin destroys cells on one side.
Guardrail: Do not import an England board, Single Award or Double Award structure, and do not replace a biological mechanism with a vague purpose statement.
Memory anchors
Reflex arc
Receptor to sensory neurone to relay neurone to motor neurone to effector.
Synapse
A gap where transmitter chemical carries a signal to the next neurone.
Accommodation
Lens-shape adjustment that focuses near or distant objects on the retina.
Insulin
A pancreatic hormone that lowers blood glucose by increasing uptake and storage.
ADH
A hormone that increases kidney water reabsorption and reduces urine volume.
Phototropism
Directional shoot growth caused by uneven auxin distribution in response to light.
Checkpoint rule
Do the check-up only after you can summarize each concept in one sentence and identify one dangerous pitfall from memory.
Knowledge Check (after reading)
Short check-up to confirm understanding of this module.
Check-up Questions
Which feature is typical of nervous rather than hormonal communication?
An endocrine gland releases a chemical messenger into the bloodstream. What type of substance has been released?
Answer all questions to submit.
Next step personalized recommendations
Continue learning
Move forward only after this module is stable.
What is Pass Harbor?
Completely free exam prep for 247 UK exams.
- Practice questions
- Flashcards
- Study guides
- Mock exams
- No registration
- No paywall
- Start instantly
“No more expensive exam prep. Quality study tools should be accessible to everyone.”