Question

1. Explain how digested fats from the lumen of the intestine enter the circulatory system. Be certain to discuss the key substances produced by the body that allow fats and lipids to be absorbed.  Also, be sure to describe how the structure of the mucosa in the intestine facilitates absorption of nutrients (that is, what are the key anatomical features that allow absorption to occur)?

Answer 1

digestion nof lipid occur in mouth with the help of lingual lipase enzymes from salivary gland.

foods rich in fat are reaching the stomach , the insoluble fat reaches small intestine, where it is acted up on by bile acids released from gall bladder with the help of cholecystokine release from the duodenum. by the action of these enzymes , the fat will transform into mixed micelles , which increases its solubility.

triacylglycerols are acted by lipase enzymes from pancreas and produces monoacylglycerols , diacylglycerols , free fatty acids , glycerol. these substances then travels through the intestinal mucosa into intestinal epithelial cells and reconverted into triacylglycerols . these then aggregates with cholestrol and apolipoprotiens to form chylomicrones , VLDL , VHDL.

The intesine wall contain small finger like projections known as villi, which contain lacteals . these are the lymphatic system which helps in absorbtion of lipid.  most of absorbtion occur in jejunum.  These are passed through lypmphatic sytstem and enter the blood stream , from here to muscles and adipose tissue cappilaries . there these are acted up on by lipoprotien lipase enzymes and form triacylglycerols , (which is stored in liver.) and free fatty acids , glycerol (stored in adipose tissue and used for fuels in muscles)

so function of gall bladder , pancrease , intestine are important for digestion of fat and its absorbtion into blood.