6. By the way, there are situations in the body when the set point can be changed!This is for example the case when one runs a fever.Then the set point is raised, because the body needs extra metabolism to battle an infection, and this increase in set point will then ‘automatically’ increase the body temperature.

1. Because the kidneys filter so much blood all the time (about 1 litre/minute!), the kidneys have a very rich blood supply. In fact, the kidneys obtain the highest portion of the cardiac stroke volume of any organ in the body: 20%!

4. The Interphase is the time between mitosis, between the cell divisions, when the cell is actually doing what it should do. This is the longest period for a cell (days to years depending on the type of cell). At the end of the interphase, when the cell has decided to divide, the chromosomes are going to be duplicated (from 2×24 to 4×24).

1. An action potential is a sudden change in the membrane potential. In the diagram, in red, the potential suddenly changes from the resting potential (approx. -90 mV; blue) to + 30 mV (red).

1. What is blood flow?. This is the amount of blood flowing through an organ or an organ system, expressed as ml or l (=litres) per minute. If you take the whole systemic circulation, then the blood flow is the same as the cardiac output: 5 L/min.

In fact, to record an ECG, you can place the recording electrodes anywhere you like as long as it is on the skin, such as on your chest, on your belly, on your foot and even on top of your head!

9. When the depolarization in the neighboring resting membrane reaches threshold, a new action potential is generated at that new location.This is indicated in panel 3; that part of the membrane now shows a full action potential with a value of +30 mV.

A. The terminal bronchioles and the alveoli. B. One Alveolus. C. The role of Surfactant. D. The respiratory membrane. E. How fast is this gas exchange?

A. Baro Reflex. B. How does the Baro reflex work? C. Wait! There is something strange here! D. Chemo reflex. E. Vascular Fluid Shift. F. The stupid Physiologist!

4. Smooth muscle action potentials in the gastrointestinal system often last very long. In the small intestine they can have a plateau that lasts for many seconds. Note here that it is the “spikes” that induce the contraction, not the action potential itself.These spikes occur in the plateau phase of the action potential.