PNB 2265 Lecture Notes - Lecture 21: Brush Border, Carboxypeptidase, Galactose
Document Summary
Set hydrogen out to interstitial fluid to get sodium using hydrogen sodium antiporter. Got rid of the sodium using sodium potassium pump. When we secretion our molecules, we are able to absorb into our body. Breakdown of complex macromolecules into smaller units by secreted enzymes. Passage of nutrients from the lumen into the tissues. Both are influenced by gi motility and secretions. Enzymatic secretion of the gi tract come from salivary glands, pancreas, stomach, and small intestine (may be zymogens) Zymogens are inactive enzymes want this because want something activated when you do digest and have food. Protective mechanism so you don"t autodigest your own tissues. Many are brush border enzymes (remain attached to the apical membrane of the intestinal epithelia) Only simple carbohydrates (monosaccharides) can be absorbed. Digest carbs and take starch and break down into disaccharides. Fructose has own way into intestinal epithelial cells, easier for it to be absorbed than galactose.