<prompt> True about histology of small intestine is AEZone of replication is in lower half of glandM cells convey microorganism to peyers patchesGALT is absent in lamina propriaSIgA provides mucosal immunity  <response>: C i.e. GALT is absent in lamina propria- Zone of replication intestinal stem cell niche is restricted to lower half of intestinal gland crypts of Lieberkuhn.- Microfold M cells are antigen transpoing cells that convey microorganisms macromolecules from intestinal lumen to Peyers patches.- Close entero endocrine cells are resting non secretory cells . Whereas open cells secrete CCK, secretin, GIP, motilin, gastrin ghrelin hormones.- GALT is prominent in lamina propria of small intestine . Secretory IgA is principle molecule of mucosal immunity 