The X and Y Chromosomes Determine Your Sex. One chromosome pair - the sex chromosomes - is unique. You don't necessarily end up with a matching pair. Typically females have two X chromosomes and males have an X and a Y. Mothers always pass an X chromosome on to their children.
On the other hand, the absorption of nonheme iron, the major dietary pool, is greatly influenced by meal composition. Ascorbic acid is a powerful enhancer of nonheme iron absorption and can reverse the inhibiting effect of such substances as tea and calcium/phosphate.
It acts as a cofactor for mucosal enzymes involved in absorption of the vitamin. 119. All of the following are required for efficient dietary absorption of vitamin B12. except. a. pepsin. b. intrinsic factor. c. hydrochloric acid.d. mucosal cobalaminase. 120.t acts as a cofactor for mucosal enzymes involved in absorption of the vitamin. 119. All of the following are required for efficient dietary absorption of vitamin B12. except. a. pepsin. b. intrinsic factor. c. hydrochloric acid.