Human physiology worksheet with answers

What is stroke volume?

1. AThe volume of blood left in a ventricle after contraction
2. BThe volume of blood ejected by a ventricle in one beat
3. CThe volume of blood pumped by the heart per minute
4. DThe volume of blood in a ventricle at the end of filling

Which enzyme in saliva starts the digestion of starch?

1. ALipase
2. BTrypsin
3. CPepsin
4. DSalivary amylase

What is tidal volume?

1. AThe air left in the lungs after a full exhalation
2. BThe maximum volume of air that can be breathed out after a full breath in
3. CThe volume of air moved in or out in one normal breath
4. DThe total volume of air in the lungs

Which ion enters the cell to cause the depolarisation phase of a typical neuronal action potential?

1. AChloride (Cl⁻)
2. BSodium (Na⁺)
3. CCalcium (Ca²⁺)
4. DPotassium (K⁺)

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

1. AIncreases about 16-fold
2. BHalves
3. CIncreases 4-fold
4. DDoubles

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

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

A patient's arterial blood gas shows pH 7.30, PaCO₂ 7.8 kPa (59 mmHg) and normal bicarbonate. What is the most likely disturbance?

1. ARespiratory alkalosis
2. BMetabolic acidosis
3. CCompensated metabolic alkalosis
4. DAcute respiratory acidosis

At the start of a fever, a patient shivers and feels cold even though body temperature is rising. Why?

1. AThe thermoreceptors in the skin are destroyed
2. BPyrogens raise the hypothalamic set point above the current body temperature
3. CSweating has already cooled the body too much
4. DThe body has lost its ability to produce heat