Hyperthyroidism occurs when the body has an overactive thyroid gland, resulting in the hypersecretion of thyroxine.
Explain why people with hyperthyroidism often experience weight loss and an increased heart rate.
Patients with hyperthyroidism have an increased risk of developing atherosclerosis, where fatty plaques build up inside the coronary arteries. Suggest why a blockage in a coronary artery can cause damage to the muscular wall of the heart.
In severe cases of untreated hyperthyroidism, a patient's core body temperature can rise above 41 ∘C41\text{ }^\circ\text{C}41 ∘C (a condition known as a thyroid storm). Explain why this extreme hyperthermia is harmful to metabolic reactions in the body.
The population of a country is 75 million. It is estimated that 2.4% of this population has hyperthyroidism. Calculate how many million people in this country have hyperthyroidism.
Thyroxine is one hormone involved in maintaining homeostasis. Name the hormone produced by the pancreas that raises blood glucose levels when they are too high.
84 exam-style questions on OCR GCSE Biology 3.2 Coordination and control – the endocrine system, covering 3.2.1 Principles of hormonal coordination and control, 3.2.2 Roles of thyroxine and adrenaline, 3.2.3 Hormones in human reproduction, 3.2.4 Interactions of reproductive hormones, 3.2.5 Hormones in contraception, 3.2.6 Hormones in reproductive technologies, 3.2.7 Plant hormones in growth and coordination, 3.2.8 Effects of plant hormones, and 3.2.9 Uses of plant hormones. Each one has a worked solution and a mark scheme showing where the marks go.