There are no well-documented examples of natural selection operating on natural populations. a. true b. false

The correct answer is B. False

Explanation:

Natural selection is one of the main processes that lead to evolution; this involves organisms in a population being more suitable to survive and reproduce due to specific traits, this causes over the time a population evolves as only organisms with certain traits survives while other organisms disappear.

Natural selection was first officially documented by Charles Darwin based on observations he made on Galapagos Islands and Argentina. Besides this, based on Darwin's proposal many scientists and biologists have documented natural selection in both natural and non-natural populations. A famous example of this is peppered moths in England that changed its color to dark due to the Industrial Revolution making trees darker and therefore making dark moths more suitable to survive. Thus, it is false there are no well-documented examples of natural selection on natural populations because over the years this phenomenon has been plenty documented.

a

explanation:

many plants naturally reproduce this way, but it can also be induced artificially. horticulturalists have developed asexual propagation techniques that use vegetative plant parts to replicate plants. success rates and difficulty of propagation vary greatly. monocotyledons typically lack a vascular cambium and therefore are harder to propagate.

the sugar-phosphate backbone forms the structural framework of nucleic acids, including dna and rna. this backbone is composed of alternating sugar and phosphate groups, and defines directionality of the molecule.