This topic summary covers Knowledge Organiser within Hormones & Behaviour for GCSE Biology. Topic 8: Hormones & Behaviour It is section 8 of 9 in this topic. Use this topic summary to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 8 of 9
Practice
15 questions
Recall
20 flashcards
Knowledge Organiser
Key Terms
- Adrenaline: Fight-or-flight hormone; from adrenal glands
- Thyroxine: Metabolic rate hormone; from thyroid gland
- Adrenal glands: Above kidneys; activated by nervous system
- Thyroid gland: In neck; controlled by TSH from pituitary
- Metabolic rate: Speed of chemical reactions in cells
- Negative feedback: Response opposes the original change
- TSH: Thyroid-stimulating hormone from pituitary
Must-Know Facts
- Adrenaline: increases heart rate, breathing rate, blood glucose; diverts blood to muscles
- Thyroxine: controls basal metabolic rate
- Thyroxine negative feedback: low thyroxine → more TSH → more thyroxine
- Hormonal response is slower but longer-lasting than nervous response
- Hypothyroidism = too little thyroxine → slow metabolism, weight gain, tiredness, feeling cold
- Adrenaline triggers glycogen breakdown in liver → raises blood glucose
- Both nervous and hormonal systems involved in fight-or-flight