Conditions under which natural selection occurs in a population of tortoises are described in the table below: Natural Selection Description Condition Description A The population comprises smaller adult tortoises and larger adult tortoise B Food is scarce on the island where the population is present Which factor contributes to natural selection for each condition? Condition A and Condition B represent competition. Condition A and Condition B represent inherited variation. Condition A represents competition, and Condition B represents inherited variation. Condition A represents inherited variation, and Condition B represents competition.

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.

sound moves fastest in solids because the molecules are tightly packed and it allows sound to vibrate