Question

Saltation and Darwinian variations respectively are
a. Large and Small
b. Directional and Directionless
c. Small and Random
d. Major variation and Minor variation

Answer 1

Hint: In biology, saltation from one generation to the next is a sudden and broad mutational transition, possibly triggering single-step speciation. Historically, this was offered as an alternative to Darwinism. Some types of mutationism, suggesting large discontinuous hops, were effectively saltationist.

Complete answer:
A mutation is a shift that occurs either due to errors when the DNA is copied or due to environmental factors such as UV light and cigarette smoke in our DNA sequence. Two forms of point mutations exist: mutations of transformation and mutations of transversion. When a pyrimidine base substitutes for another pyrimidine base or when a purine base substitutes for another purine base, transition mutations occur. Each of the bases pairs with a particular partner on the corresponding strand in double-stranded DNA; A pairs with T and C pairs with G.

Saltation is an abrupt variation, generally caused by a genetic alteration in the appearance of an organism, species, etc. Darwinian differences are that, with an accumulation of minor variations, speciation happens progressively over a number of generations. Mutations are random and directionless, while, as per Darwin, variations are small and directional. The theory of Darwin's mechanism of evolution starts with the variation between organisms within a genus. Individuals of one generation vary from each other qualitatively. For Darwin, the group 's evolution resulted from the differential survival and reproduction of individual variants that already exist in the group, variants that occur in an environmentally unrelated manner but depend on the environment for their survival and reproduction.

Hence, the correct answer is option (D).

Note: The evolution of the population as a whole is the outcome of the differing survival and reproduction rates of the different forms, such that the relative frequencies of the population vary over time. Evolution is a method of sorting, in this view.