Chemical digestion
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What this model shows
The results come from a teaching model of a strong amylase solution: the starch in bag A falls to about half in 8 minutes, and Benedict's on the water outside bag A is blue at 0 minutes, green at 10 and orange at 20. No starch ever passes the tubing, so iodine stays yellow-brown. A real experiment can take longer, depending on how much amylase is used.
In the model a protease at its own pH (pepsin at pH 2, trypsin at pH 8) clears its tube in about 10 minutes; away from that pH, and without enzyme, the tube stays cloudy. Real proteases can take longer; the pattern is the same.
The magnified view is a schematic model: real molecules and the holes in Visking tubing are far too small to see.
With reduced motion the pipettes, the droppers and the tubes do not move across the bench: each step shows its result straight away, and the bags and the tubes still change with the stop-clock.
Select a piece of equipment to read about it in the card.