This phylogenetic tree shows how scientists believe the danes, chinese, and tibetans are related based on the analysis of many genes. use the data about the epas1 alleles to add information to the tree. (assume that there is no interbreeding between the different populations after the lineages split.) labels can be used once or more than once.

voluntary muscles are controlled by the cerebellum.

it provides an alternative energy pathway for the reaction to proceed.

a catalyst is a substance that speeds up the rate of a chemical reaction but is not consumed during the course of the reaction.

catalysts increase the rate of reaction without being used up. they do this by lowering the activation energy needed. with a catalyst, more collisions result in a reaction, so the rate of reaction increases. different reactions need different catalysts.

a catalyst works by providing an alternative reaction pathway to the reaction product. the rate of the reaction is increased as this alternative route has a lower activation energy than the reaction route not mediated by the catalyst.