Starch is stored in plants and is present in Amylose and Amylopectin while glycogen is found in animals and is stored in the liver. Glycogen is an extensively branched chain of glucose molecule.
Because enzymes connect to their substrate through a lock-and-key system, where the shape of the substrate and the enzyme has to fit like puzzle pieces. Then only the enzymatic reaction can occur.
Meteorology or maybe weather forecasting
parental genotype I^o I^a × I^o I^b