Vary in the number of neutrons but Sama in the number if protons are called isotopes
The type of molecules that contains the alcohol glycerol are PHOSPHO-LIPIDS.
Glycerol is a three carbon alcohol on which some phospholipids are built. Phospholipids which are derived from glycerol are called phosphoglycerides.
The answer is B. Geology has shown a thin layer of iridium (a rare mineral on earth but found on asteroids and meteors) in the rock layers between the Cretaceous and Paleogene periods. Below this layer are numerous fossils of pterosaurs and dinosaurs, but above the layer are drastically few. The aftermath of asteroid impact is believed to have smothered most vegetation from earth which dinosaurs depended on as a source of food.
