In terms of macromolecules, needed and utilized by organisms to carry out essential metabolic chemical reactions and for maintaining structure would be Lipids.
Lipid based molecules or Fats tend to store the most energy, as breaking chemical bonds connecting fatty acid chains of long hydrocarbons releases quite a bit of energy.
Spiral galaxies fall into several classes depending on their shape and the relative size of the bulge and elliptical galaxies are placed in the categories E0-7 depending on their degree of ellipticity. they are similar because t<span>hey have a uniform luminosity and are similar to the bulge in a </span>spiral galaxy<span>, but with no disk</span>