Physiology
How the systems mapped in PCEM2 actually work, moment to moment.
The path through this topic
0 of 9 steps done.
ReadHomeostasis and feedback loopsThe single idea the whole of physiology is built on, and the two shapes a control loop can take.
5 min- ReadMembrane potential, action potential and the synapse
How a cell holds a voltage, how it inverts it in a millisecond, and how it passes the message on.
6 min - ReadThe cardiac cycle and gas exchange
One heartbeat in five phases, what sets cardiac output, and how the lung loads oxygen and unloads CO₂.
6 min - ReadRenal regulation and the endocrine axes
How the kidney sets the volume and composition of the internal environment, and how hormones are commanded.
6 min - Memo cardsPhysiology: memo cards
The whole of physiology as a deck: prompt on the front, answer on the back.
4 min 
Multiple choicePhysiology: the core mechanismsFeedback, membrane potential, the cardiac cycle and gas exchange.
5 min
Match pairsMatch hormone to effectPair each hormone with what it actually does.
4 min- Multiple choicePhysiology: harder cases
Frank–Starling, refractory periods, filtration rate and hormone action.
4 min 
Put in orderOrder the physiological sequencesRebuild the action potential and the cardiac cycle phase by phase.
5 min
The molecules behind this subject
Real structures, at the scale this chapter happens on. Rotate them on the Mechanisms page.
- Rhodopsin and retinalThe molecule that turns light into a nerve signal, and it does it by changing shape by a few angstroms.1F88
- The nicotinic receptorWhere a nerve tells a muscle to contract: five subunits round a pore that opens for a ten-thousandth of a second.2BG9
- Myoglobin and oxygenThe first protein structure ever solved, and the reason muscle is red.1MBO
- Haemoglobin, unloadedThe same molecule as the oxygenated structure, in the shape it takes once the oxygen has gone.2HHB
- ACE and lisinoprilThe drug that lowers blood pressure works by filling a hole, and here is the hole.1O86
- Haemoglobin and oxygenBlood is red because of four iron atoms, and this is what they are held in.1HHO
- InsulinFifty-one residues. The smallest thing here, and the one that decides what every cell does with sugar.1TRZ
In 3D: the Cell Lab
The cells from this course, built in 3D and cut open: touch their organelles to read their job and how they look under the microscope, then practise finding them.
Open the Cell Lab