Answer:
(B) Lava has separated the population into two areas: an upland forest and a lowland marsh.
Explanation:
In allopatric speciation, individuals of an ancestral species may undergo evolution into two or more progeny species which arises when physical separation causes a geographic boundary, this barrier can be in the form of a mountain range, rockslide, river or lava.
As in this scenario, a lava flow divides the populations of annual herbaceous plants by altering the landscape. This will cause genetic divergence with varying heritable features among its many generations favouring different traits in the separate environment along with genetic drift. The Lava will separates the population into two areas: an upland forest and a lowland marsh.
A single gene disorder is one that's known to be caused by a single gene. Multiple gene disorders, however, can be caused by multiple gene combinations and other factors. Dominant genes are always expressed in the offspring, while recessive genes are only expressed if the offspring recieves the recessive gene from both parents. Sex-linked genetic disorders occur most often in men, and are caused by a single-gene disorder gene being on the X chromosome but not the Y, so that the offspring needs only one recessive gene to have the trait/disorder.
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The embryo, endosperm and seed coat.
Nucleic acids are composed of monomers called Nucleotides
Nucleic acids are made of monomers known as Nucleotides, and there are 3 parts to Nucleotides - They are a nitrogenous base, a pentose sugar and a phosphate group