Which of the following processes rely on secondary active transport? Select all that apply. Question 4 options: Transport of chylomicrons into the lacteals Transport of di- and tri-peptide across the apical membrane Transport of single amino acids across the apical membrane Transport of fructose across the apical membrane Transport of galactose and glucose across the basolateral membrane Absorption of galactose and glucose across the apical membrane

• Transport of galactose and glucose across the basolateral membrane

Explanation:

In secondary active transport, the energy from ATP is not directly used. What happens during this process is that the electrochemical gradient of an ion that is usually established through primary active transport, is used to move the molecule across the membrane without relying on the concentration gradient hence the movement of molecule by this method is always against a concentration gradient.

Example. If there is less glucose in the lumen than in the cell and there is need for glucose, there is no possibility of moving glucose normally down the concentration gradient, however, the system takes advantage of sodium pump that moves sodium ions from lumen to the cell. Both Na+ ions and the sugar are transported into the cell on the SGLT1 transporter.