Lipids, Fats, and Biochemistry

Fats & oils are triglycerides .They are esters of fatty acids with glycerol. They are insoluble in water, non-polar in character, and are commonly called neutral fats.

These lipids are obtained on hydrolysis of simple and complex lipids. These lipids contain glycerol and other alcohols. This class of lipids include steroid hormones, ketone bodies, hydrocarbons, fatty acids, fatty alcohols, mono and diglycerides, terpenes and carotenoids. These are sometimes present as waste products of metabolism.

Spermaceti (from Greek sperma, seed, and Latin cetus, whale) sometimes erroneously called parmaceti is a wax present in the head cavities of the sperm whale (Physeter macrocephalus). Spermaceti is extracted from sperm oil by crystallisation at 6 °C, when treated by pressure and a chemical solution of caustic alkali

It is a substance used to enhance the cleansing action of water. A detergent is an emulsifier, which penetrates and breaks up the oil film that binds dirt particles and a wetting agent, which helps them to float off. Emulsifier molecules have an oil-like nonpolar portion which is drawn into the oil and a polar group that is water-soluble; by bridging the oilwater interface, they break the oil into dispersible droplets (emulsion). As a surfactant, a detergent decreases the surface tension of water and helps it penetrate soil.

Plasma membrane is composed of 'lipid and protein'. According to 'Sandwich model' monomolecular two protein layer sandwiching a bimolecular lipid layer.

The plasma membrane is composed of a phospholipid bilayer, which is two layers of phospholipids back-to-back. Phospholipids are lipids with a phosphate group attached to them. The phospholipids have one head and two tails. The head is polar and hydrophilic, or water-loving.

Monascus perpureus produces statin.

RER looks rough under a microscope because it has particles called ribosomes attached to its surface.

Reason: Pigments are stored in chromoplasts and chloroplasts (stores green pigments).

Reason: Plasma membrane is a thin molecular layer that surrounds all living cells. The plasma membrane separates the cell from its surroundings and protects it from changes in its environment. The plasma membrane is primarily composed of 2 types of molecules. (1)        Lipids - Which are fats or oil molecules. Lipids help in transporting fat soluble substances across membrane. (2)        Proteins - Help in transporting substances across the membrane.             In most cells, plasma membrane is about 40% of Lipids and 60% of protein.Vitamins like fat soluble (Vitamin A, D, E, K) or water soluble (Vitamin B, C) are not able to perform functions like lipids and proteins.Therefore they are not present in cell membrane. However, Carbohydrates along with protein e.g. glycoprotein are present in cell wall.

In practice this is a complicated procedure and so simpler methods are resorted to determine the amount of hydrogen required to convert it into a saturated fat.The simplest of these is the determination of the amount of iodine that can be made to combine with the fat. The percentage by weight of iodine absorbed by the fat in the natural state is known as the iodine number. It is an index to the degree of unsaturation of the fat.

Urine contains ketone bodies when body uses fatty acids as alternate source of fuel in condition of starvation.

Lipid molecules found in cell membranes are amiphilic molecules, with one water-soluble end, and one hydrophobic end. The water-soluble end is usually charged, while the hydrophobic end is usually one or more hydrocarbon chains. The lipids found in cell membranes are mostly molecules with two hydrocarbon chains of about 10 carbons. Lipid bilayers are made up of phospholipids that have variable head groups and fatty acid chains.The lipid bilayer acts as a very good electrical insulator and has direct bearing on the way in which the proteins embedded in the lipid bilayer will behave.

Lipids do not functions as enzymes.The function of proteins as enzymes is perhaps their best-known function. Enzymes are catalysts—they initiate a reaction between themselves and another protein, working on the molecule to change it in some way.The enzyme, however, is itself unchanged at the end of the reaction.Enzymes are responsible for catalyzing reactions in processes such as metabolism, DNA replication, and digestion.

 This is correct option as C₂₇H₄₅OH is the formula of cholesterol.