15. TEST DESCRIPTION POSITIVE RESULT NEGATIVE RESULT GREASE SPOT TEST Some oil and some water are smeared onto a piece of paper. Some time later, the water smear would become not translucent. But the smear of oil would keep translucent for a long time. formation of translucent spot on the paper. No Color Change SUDAN IV TEST Sudan red is a fat-soluble dye that stains lipids red. Using Sudan red can show the amount and the location of lipids. Red No Color Change
19. Name Gene Location Description pancreatic lipase PNLIP digestive juice In order to exhibit optimal enzyme activity in the gut lumen, HPL requires another protein, colipase , which is also secreted by the pancreas. lingual lipase ? digestive juice -
20. hepatic lipase LIPC endothelium Hepatic lipase acts on remaining lipids carried on lipoproteins in the blood to regenerate LDL ( low density lipoprotein ). lipoprotein lipase LPL or "LIPD" endothelium Lipoprotein lipase functions in the blood to act on triacylglycerides carried on VLDL (very low density lipoprotein ) so that cells can take up the freed fatty acids . gastric lipase LIPF digestive juice Functions in the infant at a near-neutral pH to aid in the digestion of lipids
There are at least five hormones that aid and regulate the digestive system in mammals. There are variations across the vertebrates, as for instance in birds. Arrangements are complex and additional details are regularly discovered. For instance, more connections to metabolic control (largely the glucose-insulin system) have been uncovered in recent years. Gastrin - is in the stomach and stimulates the gastric glands to secrete pepsinogen (an inactive form of the enzyme pepsin ) and hydrochloric acid . Secretion of gastrin is stimulated by food arriving in stomach. The secretion is inhibited by low pH . Secretin - is in the duodenum and signals the secretion of sodium bicarbonate in the pancreas and it stimulates the bile secretion in the liver . This hormone responds to the acidity of the chyme. Cholecystokinin (CCK) - is in the duodenum and stimulates the release of digestive enzymes in the pancreas and stimulates the emptying of bile in the gall bladder . This hormone is secreted in response to fat in chyme. Gastric inhibitory peptide (GIP) - is in the duodenum and decreases the stomach churning in turn slowing the emptying in the stomach. Another function is to induce insulin secretion. Motilin - is in the duodenum and increases the migrating myoelectric complex component of gastrointestinal motility and stimulates the production of pepsin .
The key players in these two transformations are bile acids and pancreatic lipase both of which are mixed with chyme and act in the lumen of the small intestine ENTROCYTES -intestinal absorptive cells, are simple columnar epithelial cells found in the small intestines and colon. A glycocalyx surface coat contains digestive enzymes. Microvilli on the apical surface increase surface area for the digestion and transport of molecules from the intestinal lumen
Bile acids are also necessary to solubilize other lipids, including cholesterol. Such coating with bile acids aids in breakdown of large aggregates or droplets into smaller and smaller droplets.
A variant of Phospholipase A 2 is secreted by the pancreas into the intestine. It hydrolyzes the ester linkage between the fatty acid and the hydroxyl on carbon 2 of phospholipids. Lysophospholipids , the products of Phospholipase A 2 reactions, are powerful detergents .
Chylomicrons are large lipoprotein particles that consist of triglycerides (85-92%), phospholipids (6-12%), cholesterol (1-3%) and proteins (1-2%). [1] They transport dietary lipids from the intestines to other locations in the body. Chylomicrons are one of the five major groups of lipoproteins (chylomicrons, VLDL , IDL , LDL , HDL ) that enable fats and cholesterol to move within the water-based solution of the bloodstream.
LPL is a water soluble enzyme that hydrolyzes triglycerides in lipoproteins, such as those found in chylomicrons and very low-density lipoproteins (VLDL), into two free fatty acids and one monoacylglycerol molecule. Some of the components of the chylomicrons are "repackaged" into other lipoproteins, for example, some apolipoproteins are transferred to High-Density Lipoprotein(HDL), and the remaining chylomicron remnant particles are removed from the plasma by way of chylomicron remnant receptors present on the liver. LPL is attached to the luminal surface of endothelial cells in capillaries. It is most widely distributed in adipose, heart, and skeletal muscle tissue, as well as in lactating mammary glands.
VLDL enable lipids like cholesterol and triglycerides to be transported within the water-based bloodstream. five major groups of lipoproteins which, in order of sizes, largest to smallest, are chylomicrons, VLDL, IDL, LDL and HDL HDL is the smallest of the lipoprotein particles. They are the densest because they contain the highest proportion of protein to cholesterol. About one-fourth to one-third of blood cholesterol is carried by high-density lipoprotein (HDL). HDL cholesterol is known as "good" cholesterol, because high levels of HDL seem to protect against heart attack. Low levels of HDL (less than 40 mg/dL) also increase the risk of heart disease. Medical experts think that HDL tends to carry cholesterol away from the arteries and back to the liver, where it's passed from the body. Some experts believe that HDL removes excess cholesterol from arterial plaque, slowing its buildup.
It is expressed in the liver and adrenal glands. One of the principal functions of hepatic lipase is to convert IDL to LDL. Each native IDL particle consists of protein that encircles various fatty acids, enabling, as a water-soluble particle, these fatty acids to travel in the aqueous blood environment as part of the fat transport system within the body they contain primarily a range of triacylglycerols and cholesterol esters. LIPC encodes hepatic triglyceride lipase, which is expressed in liver. LIPC has the dual functions of triglyceride hydrolase and ligand/bridging factor for receptor-mediated lipoprotein uptake.
too much LDL (bad) cholesterol circulates in the blood, it can slowly build up in the inner walls of the arteries that feed the heart and brain. Together with other substances, it can form plaque, a thick, hard deposit that can narrow the arteries and make them less flexible. formed from the degradation of very low-density lipoproteins. enable fats and cholesterol to move within the water-based solution of the bloodstream