Digestion and Absorption Test - 1

The Vitamin K dependent factors: III, V, VII, IX and X prolong the Prothrombin Time if deficient. Diseases affecting liver function such as cholestasis will interfere with the coagulation cascade.

A diet high in phosphates cause a decrease in the absorption of iron since compounds of iron and phosphates are insoluble; conversely a diet very low in phosphates markedly increases iron absorption.

Enterocytes function in secreting IgA. IgA is absorbed from plasma cells in the mucosa through receptor mediated endocytosis on the basolateral surface and released into the intestinal lumen.

Goblet cells are not found in stomach. There are other cells that secrete mucus (such as the foveolar cells of the stomach) but these are distinguished histologically from goblet cells.Goblet cells are present in intestinal villi along with enterocytes. They are responsible for the production and maintenance of the protective mucus blanket by synthesizing and secreting high molecular weight glycoproteins known as mucins.In the conjunctiva, goblet cells are a source of mucin in tears and they also secrete different types of mucins onto the ocular surface.Goblet cells secrete mucus in large bronchioles.

Ligament of Treitz is a thin muscle which marks the formal division between the first and second parts of the small intestine, the duodenum and the jejunum (duodenojejunal flexure).

The ileocecal valve is distinctive because it is the only site in the gastrointestinal tract that is used for Vitamin B12 absorption.

Transverse colon curves sharply at the lower end of spleen.

The anal valves are small valve-like folds at the lower ends of the anal sinuses in the rectum. They join the lower ends of the anal column.

Each villus has a network of capillaries and fine lymphatic vessels called lacteals close to its surface. The epithelial cells of the villi transport lipids from the lumen of the intestine into lacteals.

The glucose is absorbed by active transport into the villi, to be passed into the bloodstream and taken around the body.
The two ways in which glucose uptake can take place are facilitated diffusion (a passive process) and secondary active transport (an active process which on the ion-gradient which is established through the hydrolysis of ATP, known as primary active transport).
To move substances against a concentration or electrochemical gradient, a cell must use energy. Active transport mechanisms do just this, expending energy (often in the form of ATP) to maintain the right concentrations of ions and molecules in living cells.