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Edexcel IGCSE Biology · Spec 2.94-2.95B

Hormones

The endocrine system, the effects of adrenaline, and how insulin and glucagon control blood glucose.

Biology revision video

Hormones

Spec 2.94-2.95B

What you need to know

  • Describe the endocrine system
  • Explain adrenaline and blood glucose control
  • Recall the other key hormones for Triple

Active recall

Quick check

Answer each question before opening the answer.

What are the effects of adrenaline?

It increases heart rate, breathing rate and blood glucose — preparing the body for 'fight or flight'.

How is blood glucose controlled by the pancreas?

Insulin lowers it (glucose → glycogen in the liver); glucagon raises it (glycogen → glucose).

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