HUMAN PHYSIOLOGY
DIGESTION AND ABSORPTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Secondary active transport
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Active transport
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Simple diffusion
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Facilitated diffusion
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Detailed explanation-1: -The major route for the transport of dietary glucose from intestinal lumen into enterocytes is the Na+/glucose cotransporter (SGLT1), although glucose transporter type 2 (GLUT2) may also play a role.
Detailed explanation-2: -Glucose enters the epithelial cells by a process catalyzed by the cotransporter SGLT-1. Intracellular cAMP activates the transepithelial transport by a mechanism possibly involving phosphorylation of SGLT-1. The glucose accumulated intracellularly can diffuse out of the cells by facilitated diffusion through GLUT2.
Detailed explanation-3: -Glucose transporters are a wide group of membrane proteins that facilitate the transport of glucose across the plasma membrane, a process known as facilitated diffusion.
Detailed explanation-4: -GLUT2 transports glucose from the cell into the extracellular space on the basolateral side, where the glucose diffuses into capillaries. The absorption of glucose is driven by a sodium gradient maintained by basolateral Na-K-ATPase.