How is folic acid absorbed in proximal jejunum?
ANSWER: (D) Both active & passive transportREF: Harrisons 18thed chapter 105, style="font-size: 1.04761904761905em; font-family: Times New Roman, Times, serif; margin: 0 0 0 8px; text-indent: 0; text-align: left">Folates are present in natural foods and tissues as polyglutamates because these forms serve to keep the folates within cells. In plasma and urine, they are found as monoglutamates because this is the only form that can be transported across membranes. Enzymes in the lumen of the small intestine convert the polyglutamate form to the monoglutamate form of the folate, which is absorbed in the proximal jejunum via both active and passive transport.
Facilitated diffusion
Active transport
Passive transport
Both active 8t passive transport
Digestion and Absorption