Robin Burden answered
The answer really depends on what you mean by 'food molecules'.
A Visking tube has tiny holes that only allow the passage of certain molecules - sugar (or glucose) can pass through the membrane of the tube, whilst larger molecules like starch are too big to get through.
Food molecules in Visking tubes
A Visking tube is used in scientific experiments to replicate the role of the small intestine.
When food passes through this part of the stomach, tiny blood capillaries absorb glucose, minerals, amino-acids and water-soluble vitamins before they pass through.
This is a central feature of human digestion, and the holes in a Visking tube replicate this process by allowing the molecules that would be small enough to be absorbed through the blood capillaries to leak out through the porous membrane of the tube.
Because starch molecules are too big to be absorbed into the blood stream, the body relies on amylase enzymes to break starch down into more-palatable glucose.
If you're interested in reading about the use of a Visking tube in replicating the digestion of food, then this power point on slideshare.net is definitely worth a look.
A Visking tube has tiny holes that only allow the passage of certain molecules - sugar (or glucose) can pass through the membrane of the tube, whilst larger molecules like starch are too big to get through.
Food molecules in Visking tubes
A Visking tube is used in scientific experiments to replicate the role of the small intestine.
When food passes through this part of the stomach, tiny blood capillaries absorb glucose, minerals, amino-acids and water-soluble vitamins before they pass through.
This is a central feature of human digestion, and the holes in a Visking tube replicate this process by allowing the molecules that would be small enough to be absorbed through the blood capillaries to leak out through the porous membrane of the tube.
Because starch molecules are too big to be absorbed into the blood stream, the body relies on amylase enzymes to break starch down into more-palatable glucose.
If you're interested in reading about the use of a Visking tube in replicating the digestion of food, then this power point on slideshare.net is definitely worth a look.
