Arteries, veins and capillaries sim
Slide a stained artery-and-vein section under a microscope to compare the walls, lumens and capillaries at real size, take your own pressure and speed readings along the circuit, and squeeze a vein-valve model to see the valves open and shut.
Transport in humans · covers the O-Level, IGCSE, GCSE topic
What the sim shows
Model: magnification = ×10 eyepiece × objective; field 18 mm ÷ objective; actual size = image ÷ magnification (1 mm = 1000 µm). Real sizes: aorta about 25 mm, capillary 5–10 µm, red cell 7–8 µm. Mean speed = 5 L/min ÷ total cross-section: 33.3 cm/s in the aorta, 0.033 cm/s in the capillaries. Pressure 120/80 mmHg in the aorta. Values illustrative, from memory.
- The prepared slide: drag it sideways under the objective
- Dark-red coloured water: blood in a vein (dark red, never blue)
Use it in your lessons
- Try it here: anyone can unlock 2 figures free, and a free account unlocks up to 5. Runs on a laptop, a Chromebook or a phone; nothing to install.
- Present it and share student links with the teacher plan, from US$5 a month, billed yearly.
- Put it on your own website or LMS for US$9, paid once, or every sim from US$29 a month.
Free guide: 12 practicals as sims, and how to run one in a lesson →
Need a version for your exact set-up? Have one made: US$49 a figure in an order of 5.
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