27 Which of the following statements best describes the Nagl

27. Which of the following statements best describes the Na-glucose transporter of the intestinal epithelia?

A. The active transport mechanism transports both glucose and Na into the intestinal lumen.

B. The passive transport mechanism transports both glucose and Na into the intestinal lumen.

C. The active transport mechanism transports both glucose and Na into the intestinal epithelia.

D. The active transport mechanism transports glucose into the intestinal epithelia and Na into the intestinal lumen.

E. The passive transport mechanism transports glucose into the intestinal epithelia and Na into the intestinal lumen.

28. At low temperatures, bacteria will increase the number of ______ lipids in their membranes in order to increase the fluidity, or liquid nature, of the membrane.

A. saturated

B. unsaturated

C. glyco-

D. poly-

E. shorter

Explain

Solution

27. C. The active transport mechanism transports both glucose and Na into the intestinal epithelia

The Na-glucose transporter acts as a symporter which allows Na+ and glucose to enter the intestinal epithelia.

28. B. unsaturated

Unsaturated fatty acyl chains have kinks or bends, thus tend to adopt a more random, fluid state and form less van der waals interaction with other lipids. So increased proportion of unsaturated lipids will increase the fluidity of membrane at low temperature.