Mutations are spontaneous and occur at random however there are some mutagenic agents which increase the chance of this happening such as radiation exposure. If it is a point shift mutation then only a few bases on the dna sequence are changed so only changes a few of the amino acids in that chain (such as inversion of a base). If its a frame shift then the base sequence is altered so much so that every amino acid from after that changes (such as deletion of a base) which can create things such as cri-du-chat syndrome which results from a piece of chromosome 5 is missing. Hope this helps:)
Answer:
B. the combination of modern genetics and Darwinism.
Explanation:
The modern synthesis refers to the concept which combined the theory of inheritance by Mendel and theory of evolution by Charles Darwin. The theory also used the concept of Theory of germplasm.
The modern synthesis concept came in the early 20th century when the studies were going on Mendel's theory and the evolutionary aspects. The concept led to the formation of new concepts like the macroevolution, microevolution and the evolution affected by mutation of genes.
Thus, Option-B is correct.
the island is a small specie of lizards so if the mainland specie was a large population it would have been the one to be affected by an increase instead of a decrease. The genetic drift was caused by not having enough of the same kind to keep the heredity going, most likely the largest population is the one that had enough of the same heredity to keep the population of lizards going. In a way the hurricane with the force on both species caused a genetic drift but increased a larger population for a year later.
Answer: C. The sign of the enthalpy of the reaction reverses.
Explanation: Enthalpy of a reaction is the net heat absorbed or released during a chemical reaction.It is represented by 
. It is negative for exothermic reactions in which heat is released and is positive for endothermic reactions in which heat is absorbed.
When a chemical reaction is reversed the heat of the reaction changes its sign.
The decomposition of calcium carbonate is an endothermic reaction as heat is required to break the bonds and thus energy is absorbed.
When the reaction is reversed, the reaction becomes exothermic as now bonds are getting formed and energy is released.
