Glucose absorption, reabsorption and transport mechanisms

Practice Question Solving
1

Hey!

I am facing difficulties with the topic of glucose absorption in the digestive system and the renal system. Many resources are giving different answers.
I am unsure where GLUT is used and where is SGLT and whether it is facilitated diffusion or secondary active transport. If someone can help me with summarizing this topic I would be very thankful, just tell me how is glucose absorbed at this specific location and is it passive or active and GLUT or SGLT

In addition just to check, galactose is for sure absorbed in the small intestine by facilitated diffusion and by SGLT and fructose in small intestine is active and by GLUT. This info is correct right?

Thank you in advance for whoever will help me!

2

On the topic of GLUT and SGLT I am quite unsure myself, but glucose is absorbed by active transport, specifically with the Na/K pump, in the intestine and (the way i remember it) with SGLT. Here’s a summary of how it works.

From the intestinal lumen, glucose (active transport, SGLT), galactose (active transport, SGLT) and fructose (facilitated diffusion, GLUT) pass through the apical membrane of the enterocytes (intestinal epithelial cells). Once they are in the enterocytes, they ALL further pass into the capillaries by facilitated diffusion, by GLUT (again, all of them). These capillaries then eventually form the hepatic portal vein.

Hope this helps!