• Two leak-proof bags were set up. • One bag was made from artificial partially permeable membrane (Visking tubing). • The other bag was made from a piece of small intestine containing living cells, with its inner surface inside the bag. • The bags were filled with equal volumes of a dilute glucose solution. • The bags were suspended in the same glucose solution for two hours. • After two hours, the volumes of the bags were measured and the contents were tested for the concentration of glucose. Inside the bag made from small intestine the volume and concentration of the glucose solution decreased. There were no changes to the volume and concentration in the Visking tubing bag. (c) State and explain the process responsible for the decrease in the glucose concentration in the bag made from small intestine.

The process by which the concentration of the glucose in the bag made from small intestine decreased is aerobic respiration.

Aerobic respiration is the process by which cells breaks down glucose in the process of oxygen to release energy for their metabolic needs.

Explanation:

Living things respire, that is they break down nutrients to produce energy for metabolic activities.

The bag made from visking tubing is made of non-living materials which do not respire. Therefore, the glucose concentration in it remains constant. However, for the bag made of small intestine containing living cells, the living cells will carry out aerobic respiration using the glucose molecules found in the glucose solution. During this process, glucose is broken down in the presence of oxygen to release energy for the cells. Therefore, the glucose concentration in the bag will decrease.