Human physiology worksheet with answers

Which blood vessels have valves that prevent blood flowing backwards?

1. ACapillaries
2. BVeins
3. CArteries
4. DArterioles

What is normal core body temperature in an adult, approximately?

1. A37 °C
2. B38.5 °C
3. C35 °C
4. D36 °C

What is the typical resting membrane potential of a neuron?

1. AAbout −10 mV
2. BAbout −70 mV
3. CAbout +70 mV
4. DAbout 0 mV

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

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

How does glucagon raise blood glucose?

1. AIt stimulates glycogen breakdown and gluconeogenesis in the liver
2. BIt blocks insulin receptors on fat cells
3. CIt slows glucose absorption from the gut
4. DIt stimulates glucose uptake by muscle

Which protein forms the mesh that stabilises a blood clot?

1. AThrombin
2. BCollagen
3. CAlbumin
4. DFibrin

In pernicious anaemia, autoimmune destruction of gastric parietal cells leads to anaemia because:

1. AAcid is lost, so iron is never absorbed in any form
2. BIntrinsic factor is lost, so vitamin B12 is not absorbed
3. CGastrin is lost, so the bone marrow is no longer stimulated
4. DPepsin is lost, so haemoglobin cannot be made

According to the length–tension relationship, why does a skeletal muscle fibre produce less force when overstretched?

1. AActin and myosin overlap less, so fewer cross-bridges form
2. BThe muscle runs out of ATP when stretched
3. CThe neuromuscular junction stops working
4. DCalcium is no longer released from the sarcoplasmic reticulum when stretched