Reabsorption of most glucose and amino acids in the filtrate accomplished by
A)countertransport
B)secondary active transport
C)passive transport
D)secretion
E)facilitated diffusion
B)secondary active transport
The reabsorption of most glucose and amino acids in the filtrate is accomplished by option B) secondary active transport.
Secondary active transport is a process where the movement of one substance is coupled to the movement of another substance across a cell membrane. In the case of glucose and amino acids reabsorption, they are transported across the renal tubules along with sodium ions by secondary active transport.
The reabsorption of these molecules occurs in the proximal convoluted tubule of the nephron in the kidney. Sodium ions are actively transported out of the tubule cells into the interstitial fluid. As a result, a concentration gradient of sodium ions is created, which facilitates the movement of glucose and amino acids against their concentration gradients.
Glucose and amino acids are moved from the renal tubule into the tubule cells by co-transporter proteins, such as the sodium-glucose co-transporter (SGLT) and the sodium-amino acid co-transporter (SAAT). These co-transporters use the energy stored in the sodium concentration gradient to move glucose and amino acids into the tubule cells. Once inside the tubule cells, these molecules can be transported out of the cells and into the interstitial fluid by facilitated diffusion.
Overall, the reabsorption of most glucose and amino acids in the filtrate is accomplished by secondary active transport, utilizing co-transporter proteins and the sodium concentration gradient.