GCSE Biology: Homeostasis & Response — Deep Revision Workbook

Inside GCSE Biology: Homeostasis & Response — Deep Revision Workbook

master homeostasis, negative feedback and temperature control, work through the nervous system, reflexes and the eye, revise the endocrine system and blood glucose control, then tackle reproduction hormones, plant tropisms and higher-tier thyroxine feedback, before an extended exam-style 6-marker. About 45 minutes.

Learning objectives

• homeostasis, feedback and temperature — receptors, coordination centre and effectors, negative feedback, and thermoregulation with shivering, vasoconstriction and sweating;
• the nervous system and the eye — the reflex arc, synapses and neurotransmitters, and the cornea, retina, accommodation and correcting myopia;
• the endocrine system and blood glucose — the pituitary, thyroid and adrenal glands, and insulin, glycogen, glucagon and Type 1 versus Type 2 diabetes;
• reproduction, plants and higher feedback — FSH, LH, oestrogen and progesterone, IVF, phototropism and auxin, and thyroxine control of metabolic rate;
• extended exam application — a 6-mark answer on temperature control as negative feedback and applying blood glucose control to Type 1 diabetes.

Activities in this book

1. Section 1 — Homeostasis, Negative Feedback & Temperature

   homeostasis keeps internal conditions constant using receptors, a coordination centre and effectors. Negative feedback reverses any change: if a level rises, the body acts to lower it, and vice versa. Body temperature is monitored by the thermoregulatory centre — too hot means sweating and vasodilation; too cold means shivering and vasoconstriction.

2. Section 2 — Nervous System, Reflexes & the Eye

   the reflex arc runs stimulus → receptor → sensory neurone → relay neurone → motor neurone → effector, with a synapse between neurones where a neurotransmitter carries the signal. In the eye, the cornea and lens refract light onto the retina; changing the lens shape to focus is accommodation.

3. Section 3 — Endocrine System & Blood Glucose

   the endocrine system releases hormones from glands into the blood: the pituitary is the master gland, the thyroid makes thyroxine, and the adrenal glands make adrenaline. The pancreas controls blood glucose — insulin lowers it (storing glucose as glycogen) and glucagon raises it.

4. Section 4 — Reproduction, Plants & Higher Feedback

   four hormones control the menstrual cycle: FSH matures an egg, oestrogen builds the uterus lining, an LH surge triggers ovulation, and progesterone maintains the lining. Plant hormones (auxin) control tropisms — growth towards light (phototropism) or gravity. Thyroxine is controlled by negative feedback.

5. Section 5 — Extended Exam-Style Application

   exam questions reward joined-up biology: name each part in the right order and link it to the next. For a 6-mark question, plan four or five clear points, use the correct key terms, and answer every part of the question.

Suggestions for teaching

• Start with the loop. Make sure learners can name receptor, coordination centre and effector for every example before moving on.
• Model both directions of feedback. Walk through too hot (sweat, vasodilation) and too cold (shiver, vasoconstriction), and glucose rising (insulin) and falling (glucagon).
• Sequence the reflex arc. Have learners recite stimulus → receptor → sensory → relay → motor → effector, placing a synapse between neurones.
• Order the four cycle hormones. FSH (mature egg) → oestrogen (build lining) → LH (ovulation) → progesterone (maintain lining).
• Practise the 6-marker. Model a full, ordered answer aloud before writing, marking one point per correctly linked idea.