Human physiology worksheet with answers

Which hormones are the main regulators of the body's basal metabolic rate?

1. AMelatonin and serotonin
2. BThyroid hormones (T3 and T4)
3. COestrogen and progesterone (ovarian steroids)
4. DInsulin and glucagon

Exchange of gases and nutrients between blood and tissues happens mainly across the walls of:

1. AVeins
2. BArterioles
3. CCapillaries
4. DArteries

Which ion triggers contraction by binding to troponin in skeletal muscle?

1. AChloride
2. BSodium
3. CPotassium
4. DCalcium

According to Poiseuille's law, if the radius of an arteriole halves, its resistance to flow:

1. AHalves
2. BDoubles
3. CIncreases about 16-fold
4. DIncreases 4-fold

Which hormone is released by the adrenal cortex in response to ACTH?

1. AThyroxine
2. BAdrenaline
3. CAldosterone, as the main response
4. DCortisol

Why do myelinated axons conduct action potentials faster than unmyelinated ones?

1. AThe impulse jumps between nodes of Ranvier
2. BMyelin makes the axon thinner
3. CMyelin releases neurotransmitter along the axon
4. DMyelin contains more sodium channels

Why is severe hyperkalaemia dangerous for the heart?

1. AIt depolarises cardiac cells, inactivating sodium channels and causing arrhythmias
2. BIt speeds up the SA node until tachycardia causes fainting
3. CIt blocks the binding of calcium to troponin
4. DIt hyperpolarises cardiac cells, so they can never fire

Spirometry shows reduced FEV1 and reduced FVC, with a normal or high FEV1/FVC ratio. What pattern is this?

1. AA restrictive pattern, as in pulmonary fibrosis
2. BAn obstructive pattern, as in emphysema or chronic bronchitis
3. CAn obstructive pattern, as in asthma
4. DA normal result in an older adult