Who this is for: Cambridge IGCSE Biology (0610) students who want hormones in humans — endocrine glands, adrenaline and blood glucose control — to become reliable marks instead of a list they confuse with the nervous system.
What query it owns: how to understand and revise hormones in humans in Cambridge IGCSE Biology.
Why this is safe: this page owns the hormones-in-humans revision-guide angle, while Tutopiya’s Hormones in Humans subtopic page owns the learning resource and the free Hormones in Humans quiz owns the practice.

Hormones are chemical messengers secreted by endocrine glands into the blood, travelling to target organs where they bring about a response. Cambridge IGCSE Biology (0610) tests whether you can name key hormones, state their source and effect, and compare hormonal with nervous coordination. This guide covers the syllabus hormones, the adrenaline response, and the question types that appear every year.

Key takeaways

• Hormones are chemical messengers carried in the blood to target organs.
• Hormonal coordination is slower but longer-lasting than the nervous system.
• Adrenaline prepares the body for fight or flight (increased heart rate, breathing, blood to muscles).
• Insulin lowers blood glucose; glucagon raises it — both from the pancreas.
• Exam answers must state gland, hormone and effect together.

What are hormones in humans in Cambridge IGCSE Biology?

Hormones are chemicals produced by endocrine glands, released directly into the bloodstream, and carried to specific target organs where they cause a response. Unlike nerve impulses, hormones act more slowly but have longer-lasting effects. Key examples include adrenaline (adrenal glands), insulin and glucagon (pancreas), testosterone (testes) and oestrogen (ovaries).

You can read the full explanation, worked examples and notes on Tutopiya’s Hormones in Humans subtopic page before you attempt questions.

The core ideas you must master

Idea	What it means	How the exam uses it
Endocrine gland	Ductless gland secreting hormones into blood	”Name the gland that produces insulin”
Target organ	Organ with receptors for a specific hormone	”State the target organ of adrenaline”
Adrenaline response	Fight-or-flight preparation	”Describe the effects of adrenaline”
Blood glucose control	Insulin lowers, glucagon raises	”Explain how blood glucose is regulated”
Nervous vs hormonal	Speed, duration, pathway differences	”Compare nervous and hormonal coordination”

Key hormones you must know

Hormone	Gland	Effect
Adrenaline	Adrenal glands	Increases heart rate, breathing rate, blood flow to muscles; prepares for danger
Insulin	Pancreas	Lowers blood glucose (converts glucose to glycogen in liver)
Glucagon	Pancreas	Raises blood glucose (converts glycogen to glucose in liver)
Testosterone	Testes	Develops male secondary sexual characteristics
Oestrogen	Ovaries	Develops female secondary sexual characteristics

Nervous vs hormonal coordination

Feature	Nervous system	Hormonal system
Signal type	Electrical impulses	Chemical hormones
Pathway	Neurones	Bloodstream
Speed	Very fast	Slower
Duration	Short-lived	Longer-lasting
Target	Specific muscles/glands	Target organs with receptors

Hormones in past-paper wording: command words that matter

Command word / phrase	What the question wants	Typical hormone stem
Define	Precise syllabus definition	”Define a hormone.”
State	Short factual answer	”State the gland that secretes adrenaline.”
Describe	Effects step by step	”Describe the effects of adrenaline on the body.”
Explain	Cause and effect	”Explain how insulin controls blood glucose.”
Compare	Similarities and differences	”Compare nervous and hormonal coordination.”

Worked exam-style stems (how to answer the wording)

1. “Define a hormone.” A hormone is a chemical substance produced by an endocrine gland, transported in the blood, that acts on a target organ. Mark-scheme reward: chemical, endocrine gland, blood, target organ.
2. “Describe the effects of adrenaline on the body.” Increases heart rate, increases breathing rate, increases blood flow to muscles, dilates pupils, converts glycogen to glucose. Reward: at least three named effects.
3. “Explain how insulin controls blood glucose concentration.” After a meal, blood glucose rises → pancreas secretes insulin → liver converts glucose to glycogen → blood glucose falls. Reward: stimulus → hormone → effect chain.

When you can recognise the wording instantly, work the full set on the Coordination and Response topical past paper questions and the Hormones in Humans quiz to lock the definitions in.

How hormones connect to the rest of the syllabus

Hormones link to Homeostasis (blood glucose and temperature control), Sense Organs and Sexual Hormones in Humans. The Cambridge IGCSE Biology resource hub links every Coordination subtopic.

Common mistakes students make

• Confusing insulin (lowers glucose) with glucagon (raises glucose).
• Describing adrenaline as acting through neurones instead of the bloodstream.
• Omitting the target organ in hormone explain questions.
• Saying hormones act faster than nerve impulses (the opposite is true).
• Mixing up testosterone and oestrogen sources or effects.

When you need more support

If hormone questions keep costing marks — especially insulin/glucagon explain chains — work through the Coordination and Response topical past paper questions and the Hormones in Humans quiz, then get focused help from a Cambridge IGCSE Biology tutor.

Frequently asked questions

Is hormones in humans hard in Cambridge IGCSE Biology? The individual hormones are manageable, but marks are lost when students confuse insulin with glucagon or omit gland and target organ in answers.

What is the difference between insulin and glucagon? Insulin lowers blood glucose by converting glucose to glycogen; glucagon raises blood glucose by converting glycogen back to glucose.

How does adrenaline differ from a nerve impulse? Adrenaline is a chemical hormone carried in blood with slower but longer-lasting effects; nerve impulses are electrical and act very quickly along neurones.

How do I revise hormones effectively? Learn each hormone as gland → hormone → effect, compare nervous vs hormonal coordination, then take the Hormones in Humans quiz.

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