Question

what is the location, structure, and function of the brush border cells?

what is special about fat absorption?

how many different cell types use carbonic anhydrase?

how is the generic structure of the alimentary canal modified in the stomach?

Answer 1

Answer 1

Location- Small Intestine

Sturcture -  the microvilli are referred to as striated border and are protoplasmic extensions contrary to villi which are submucosal folds, while in the kidneys, microvilli are referred to as brush border

Function -  which further increase the total area for absorption. Absorbed nutrients are moved into circulation by blood capillaries and lacteals, or lymph channels.

Answer 2

The products of lipid digestion enter the body by a different process and a different route. These products namely, long chain fatty acids, monoglycerides and diglycerides are insoluble in water and cannot be directly absorbed from intestinal contents. They combine with the bile salts and phospholipids to form small spherical water-soluble molecular aggregates called micelles. From the micelles, fatty acids, glycerides and fat-soluble vitamins are actively absorbed into the intestinal cells. In these cells, the bile salts are freed and fatty acids, glycerol, monoglycerides and diglycerides are resynthesized into fats. The fats are then mixed with cholesterol and coated with special proteins forming small globules called chylomicrons The latter are transported by exocytosis out of the epithelial cells into a lacteal.

Answer 3

Three

Answer 4

Stomach lacks serosa layer, instead of it adventia layer is present which is thin.

inner mucuosa layer containg enzyme producing gland

Submucuosa contain brunners gland special to stomach