Question

Which of the following is not true for a species?
a. Members of species can be interbred
b. Variation occur among members of species
c. Each species is reproduced isolated from every other species
d. Gene flow does not occur between the population of species

Answer 1

Hint: A species is the basic classification unit, and an organism's taxonomic rank, as well as a biodiversity unit. They show a significant level of incorporation into the essence of living.

Complete answer:
> Option A is incorrect. Species are the ones capable of interbreeding between themselves. These are inextricably connected. Because of interbreeding the offspring produced will be fertile in nature. The incorporation (by interbreeding) of genetic material from one given species into another, thus changing the composition of the gene pool of the recipient population. The emergence of new alleles through the flow of genes increases diversity within the population and allows new combinations of traits possible.

> Option B is incorrect. Variation is seen in the members of the same species and may contribute to natural selection. Any distinction among cells, individual organisms, or groups of organisms of any type caused either by genetic variations (genotypical variation) or by the influence of environmental factors on the genetic potential expression (phenotypical variation).

> Option C is incorrect. Reproductive isolation is a set of mechanisms, actions, and physiological processes that prevent members of two distinct species crossing or matting from producing offspring or ensuring that any offspring that can be produced is not fertile. This can be caused by differences in mating, sterility or environmental barriers which eventually lead to the adaptive splitting into two species. However, reproductive isolation is not sufficient because for speciation to evolve, internal barriers to gene flow are important.

> Option D is correct. Gene flow is the movement of genetic material from one to another population. Gene flow can take place through migration between two populations of the same species, and is mediated by reproduction and vertical transfer of genes from parent to offspring. There is gene transfer between a species' populations. Within plant species, for example, gene flow may occur when pollen is carried by bees or blown by wind from one flowering plant population to another of the same species.

Hence, The correct answer is option (D).

Note: A species is very often described as the largest group of organisms where any two individuals of the respective sexes or types of mating can produce fertile offspring, usually through sexual reproduction.