Answer:
A change in pH will cause many cellular processes to be disrupted because they affect the biomolecules (protein and nucleic acid) responsible for these processes.
Explanation:
pH refers to the degree of acidity or alkalinity. In a cell, the structures and processes that occur in them are impossible without the biomolecules, which are carbohydrate, protein, lipids and protein.
However, unfavorable conditions like a change in pH can cause the structure of some of these biomolecules to be affected. Proteins are made up of amino acids, which gives them their shape that is peculiar to their functioning. Also, nucleic acids such as DNA are composed of nucleotides responsible for their functioning.
A change in pH will cause the bonds of the protein to be disrupted, hence altering its shape and ultimately its functioning. Likewise, the hydrogen bonds in the DNA will be broken in the presence of a high pH causing the DNA to be dysfunctional.
When these biomolecules are affected, the vital functions that they perform in a cell, which is key to the cell's survival are disrupted) are likewise affected. Therefore, the cell is affected negatively.
The answer is stabilizing selection.
<span>Sickle-cell anemia is a recessive disorder caused by the presence of two recessive alleles "s", so genotype is "ss". This disorder is characterized by sickle hemoglobin. In an area with malaria, heterozygous individuals "Ss" (with one dominant allele and one recessive allele) have an advantage. These individuals will have both normal and sickle hemoglobin. But pathogen that causes malaria affect only normal hemoglobin, so heterozygous individuals will have half of the hemoglobin resistant to the pathogen and those individuals are resistant to malaria.</span>
Stabilizing selection favors heterozygotes Ss, disruptive selection favors dominant (SS) and recessive (ss) homozygotes, while directional selection favors dominant (SS) or recessive (ss) homozygote. Since in this example, people with genotype Ss (heterozygotes) are in advantage, then this is an example of stabilizing selection.
The answer to your question is D
Scientists<span> are people who use research and experiments to learn more about the natural world. </span>Scientists<span> use scientific methods to derive knowledge systematically, performing repeatable experiments to ensure that their conclusions are valid and accurate.</span>