Tag: functions of lipids

Lecithin is a group of yellow-brownish fatty substances present in animal and plant tissues.In the pharmaceutical industry, it is used in emulsifications and encapsulation of drugs and is a good dispersing agent. Thus the correct answer is option A.

Phosphatidylethanolamines are phospholipids found in all living cells, They are found mainly in the nervous tissue such as the white matter of the brain, nerves, neural tissue and in the spinal cord. 

Membrane biogenesis is structuring/rebuilding/repairing of the cell membrane. As the cell membrane is made of a bilayer of phospholipids embedded with proteins.It is a process carried out by the cell with the help of smooth endoplasmic reticulum (SER) and Golgi apparatus (GA). Where the SER synthesizes lipids which are added with phosphate group and modified to phospholipids by the process of phosphorylation in the GA and transported through vesicles to the cell membrane.

De novo synthesis of cholesterol from acetyl-CoA takes place in the liver. Cholesterol is an essential metabolite for the normal functioning of the endocrine system, regulation of cell membrane processes, and absorption of dietary lipids. They are important structural components of membranes. Cholesterol also serves as precursor for the synthesis of steroid hormones, vitamin D, and bile salts which are important in fat absorption from the small intestine into the blood circulatory system and secretion of liver waste products through feces. Thus the correct answer is option B.

Commonly candles are prepared from stearic acid and paraffin wax. Candles that made from paraffin wax only burn quicker than those made from paraffin wax and stearic acid together.

Turpentine oil is an oil which is a volatile oil which is mainly obtained from pines a gymnospermic plant. It is obtained by distillation of resin. Terpenes are the derivative of terpene oil. It is used for thinning oil based paints. It is a very good source of organic synthesis. It is highly viscous in nature. The solid material left behind after distillation is known as rosin.

Lipid bilayer of the cell membrane contains hydrophilic head groups facing outward and hydrophobic tails facing each other. The transport of phospholipids and lipid-linked oligosaccharides is difficult to achieve due to this bipolar nature. The transmembrane lipid transporter proteins called flippases transport lipids across cell membrane through transverse diffusion by flipping their orientation. Floppases transport in reverse direction. In mammals, this affects various processes such as blood coagulation, immune recognition, and programmed cell death.Most protein molecules do not flipflop due to their extensive polar regions, which are unfavorable in the hydrophobic core of the membrane.