What are hormones? Name the gland, the hormone and one job for growth, metabolism, blood sugar and emergencies. Explain the feedback control of insulin.

1. 1 · Define in one line. Hormones are chemical messengers released by endocrine glands directly into the blood.
2. 2 · Why hormones are needed. They reach every cell, unlike nerve impulses, which reach only connected cells.
3. 3 · Make a table.
   • Pituitary: growth hormone: growth; too little causes dwarfism.
   • Thyroid: thyroxin: metabolism; needs iodine.
   • Pancreas: insulin: lowers blood sugar.
   • Adrenal glands: adrenaline: prepares the body for emergencies.
4. 4 · Feedback mechanism. Blood sugar rises → pancreas releases more insulin → sugar falls → less insulin is released.
5. 5 · Draw the feedback flow chart. [Flow chart: blood sugar rises → more insulin → blood sugar falls → less insulin]
6. 6 · Link to daily life. Iodised salt prevents goitre; many people with diabetes take insulin injections.
7. 7 · Close in one line. Hormones and feedback keep the body's internal conditions steady.

Scoring tip: A four-row table of gland, hormone and job is quick to write and easy to mark.