Lipids are part of a group of large molecules called macromolecules.Lipids are macromolecules that contain carbon, hydrogen and oxygen.Lipids are commonly known as fats or oils. Fats are solid at room temperature and oils are liquid at room temperature.They are non-polar molecules and insoluble in water, but soluble in organic solvents such as ethanol.Unlike polysaccharides like starch, cellulose and glycogen, lipids are not made from repeating units(monomers) and are therefore macromolecules but not polymers.
Cell membranes and membranes of organelles are made of phospholipids.Phospholipids are lipids that contain a charged phosphate group and so are soluble in both polar and non-polar solvents.Lipids have other roles such as a source of energy, waterproofing, electrical and thermal insulation and the protection of vital organs such as the heart and kidneys.Lipids are metabolic source of water for organisms living in dry environments.
Cell membranes and membranes of organelles are made of phospholipids.Phospholipids are lipids that contain a charged phosphate group and so are soluble in both polar and non-polar solvents.Lipids have other roles such as a source of energy, waterproofing, electrical and thermal insulation and the protection of vital organs such as the heart and kidneys.Lipids are metabolic source of water for organisms living in dry environments.