In biology and biochemistry, a lipid is a macro-biomolecule that is soluble in nonpolar solvents. Non-polar solvents are typically hydrocarbons used to dissolve other naturally occurring hydrocarbon lipid molecules that do not (or do not easily) dissolve in water, including fatty acids, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E, and K), monoglycerides, diglycerides, triglycerides, and phospholipids. …

Preparation tricks for GRE are described here: GRE Quant Prep Advice Start with Math concepts books like Manhattan/Kaplan or Magoosh books. These concepts books will give you good foundations of math topics, formula, and how concepts are tested.   Then move to ETS Official GRE books to get the feeling of …

The primary aim of culture preservation is to maintain the organism alive, uncontaminated, and without variation or mutation, that is, to preserve the culture in a condition that is as close as possible to the original isolate. Once a microorganism has been isolated and grown in pure culture, it becomes …