Derived lipids - class-XII

Sterols are classified as lipids because they are hydrophobic and soluble in organic solvents. Cholesterol is the most well-known sterol and serves as a fundamental component of cell membranes.

Cholesterol is a precursor for bile salts, Vitamin D, and steroid hormones. Insulin is a protein hormone, not a steroid, and is not derived from cholesterol.

Biological membranes are made up of lipid bilayer. These sterols affects the fluidity and rigidity of the membrane. At physiological temperature, sterols in biological membranes increase their fluidity but makes them more stronger and rigid. Environmental conditions like higher temperatures or unsaturated fatty disrupts close packing of lipids. This results in increase in the fluidity of the membrane. The membranes become more permeable to water. However, at lower temperatures, membranes become rigid. 

Cholesterol acts as precursor of Vitamin D and steroid hormones like estrogen, testesterone

Masculinisation is a side-effect which is not commonly observed in females due to the intake of anabolic steroids. so, 'the correct option is - masculinisation'. "So, the correct answer is 'A' ".

Cholesterol helps to keep the membrane stable. This stability is maintained  as: At high temperatures, cholesterol reduces membrane fluidity by restraining the movement of phospholipids. At low temperatures, cholesterol gives solidification of the membrane because it prevents the close packing of phospholipids.

Cholesterol content is minimum in vegetable oils as plant have ergosterol as the major sterol present in them. Cholesterol is present in animals and 20 % of total cholesterol is sythesised in liver.

The steroids are composed of seventeen carbon atoms, bonded in four fused rings: three six-membered cyclohexane rings and one five-membered cyclopentane ring. The steroids differ in the functional group attached to this four-ring core and by the oxidation state of the ring.

In the fluid mosaic model, the phospholipid bilayer has integrated as well as peripheral proteins embedded in it. The integrated proteins are found on the inside and span across the bilayer, while the peripheral proteins are found at the periphery of the lipid layers.

So the correct answer is 'has proteins embedded in it'.

Its main functions are the synthesis of lipids, steroid hormones, the detoxification of harmful metabolic byproducts and the storage and metabolism of calcium ions within the cell. The smooth ER is distinguished from the other parts of the endoplasmic reticulum by the absence of membrane-bound ribosomes.

CPPP is the abbreviated form of Cyclopentanoperhydrophenanthrene. It is an important component of sterol. Thus the correct answer is option A.

Steroids are hormonal substances in animals, but they are components of membranes in most organisms. Triterpenes are precursors to steroids in both plants and animals. Steroids are derivatives of triterpenes with 26 or more carbon atoms that have undergone a characteristic type of rearrangement.
So, the correct answer is option C.