If Huntington's disease is due to a dominant trait, shouldn't three-fourths of the population have Huntington's while one-fourth
has the normal phenotype? In large populations, Mendelian ratios are ineffective. Appearance of a trait in a population does not solely depend on its dominant or recessive nature. Natural selection is eliminating Huntington’s disease.
Appearance of a trait in a population does not solely depend on its dominant or recessive nature.
Explanation:
The appearance of a trait in a population is not only dependent on its dominant or recessive nature.
Huntington's disease is caused by a mutation in the gene that encodes a protein called huntingtin (Htt). This mutation produces an altered form of the Htt protein, which causes the death of nerve cells (neurons) in certain brain regions. Even if caused by a dominant gene, Huntington's disease will only be expressed in 50% of people who inherit this gene from their parents. This will depend on the organism's gene expression and other factors besides the dominant character of this gene.
It follows that the carnivores (secondary consumers) that feed on herbivores and detritivores and those that eat other carnivores (tertiary consumers) have the lowest amount of energy available to them.
Nitrogen group element, any of the chemical elements that constitute Group 15 (Va) of the periodic table. The group consists of nitrogen (N), phosphorus (P), arsenic (As), antimony (Sb), bismuth (Bi), and moscovium (Mc).
