Question

What characterize lipids

Answer 1

A hydrophobic hydrocarbon made up of carbon (C) and hydrogen (H). It is usually very large molecule that will not mix with water making it hydrophobic. If you try to mix oil and water the two don't mix.
2) Lipids are not made from small subunits into a long molecular chain. Lipids are not polymers.

Simple lipids:
1) Neutral fats & oils are triglycerides (3 fatty acids attached to a single glycerin). Esters of three molecules of fatty acids plus one molecule of glycerol; the fatty acid may all be different. The nature of the lipid triglyceride depends on the fatty acid chains.
Triglycerides are found in insulating adipose tissue and as a compact energy source in butterfat, lard, suet, fish oils, olive oil, corn oil, etc.

2)Lipid Waxes (bee honey-combs, plant cuticle coating, hair coating like lanolin) serve as surface coatings to provide protection or lubrication.

Compound lipids:
3) Steroids (cholesterol -> aldosterone, cortisone, testosterone, progesterone and estrogen) Cholesterol’s carbon skeleton with four fused rings is a precursor for biosynthesis of sex hormones and a critical membrane constituent.

4) Phospholipids and glycolipids (cell membrane compound lipids)are amphipathic diglycerides with a phosphate head group so they are not neutral.They have a polar end making them form a bilayered membrane.