Answer:
C. The substance does not directly harm tissues and is not a pathogen, but nevertheless triggers an inflammatory response.
Explanation:
When a person is allergic to a substance, his or her immune system recognizes a harmless substance, such as components in food, pollen, or dust, as a treat. As a consequence, it starts an immune response that leads to inflammation. The substance that starts the allergic reaction is called an allergen, and it is not a pathogen because it is not a real threat to the body since it does not infect cells. When the allergen enters the body, it binds to antibodies that are in contact with a special type of cell. These specific cells will release a substance known as histamine. Histamine will produce an inflammatory reaction affecting different tissues in our body. For example, it can make us sneeze, have a running nose, swelling parts of our body, have itchiness and redness, amongst others.
The tricuspid valve, located between the right atrium and the right ventricle; the pulmonary (pulmonic) valve, between the right ventricle and the pulmonary artery; the mitral valve, between the left atrium and left ventricle; and. the aortic valve, between the left ventricle and the aorta.
Answer:
So one partner has genotype: Aa or AA while the other without dimples has: aa
There can be children with dimples only if the first partner with dimples has as genotype Aa.
The DNA polymerases are enzymes that create DNA molecules by assembling nucleotides, the building blocks of DNA. These enzymes are essential to DNA replication and usually work in pairs to create two identical DNA strands from one original DNA molecule. During this process, DNA polymerase “reads” the existing DNA strands to create two new strands that match the existing ones.
Every time a cell divides, DNA polymerase is required to help duplicate the cell’s DNA, so that a copy of the original DNA molecule can be passed to each of the daughter cells. In this way, genetic information is transmitted from generation to generation.
Before replication can take place, an enzyme called helicase unwinds the DNA molecule from its tightly woven form. This opens up or “unzips” the double stranded DNA to give two single strands of DNA that can be used as templates for replication.
DNA polymerase adds new free nucleotides to the 3’ end of the newly-forming strand, elongating it in a 5’ to 3’ direction. However, DNA polymerase cannot begin the formation of this new chain on its own and can only add nucleotides to a pre-existing 3'-OH group. A primer is therefore needed, at which nucleotides can be added. Primers are usually composed of RNA and DNA bases and the first two bases are always RNA. These primers are made by another enzyme called primase.
Although the function of DNA polymerase is highly accurate, a mistake is made for about one in every billion base pairs copied. The DNA is therefore “proofread” by DNA polymerase after it has been copied so that misplaced base pairs can be corrected. This preserves the integrity of the original DNA strand that is passed onto the daughter cells.

A surface representation of human DNA polymerase β (Pol β), a central enzyme in the base excision repair (BER) pathway. Image Credit: niehs.nih.gov
Structure of DNA polymerase
The structure of DNA polymerase is highly conserved, meaning their catalytic subunits vary very little from one species to another, irrespective of how their domains are structured. This highly conserved structure usually indicates that the cellular functions they perform are crucial and irreplaceable and therefore require rigid maintenance to ensure their evolutionary advantage.
Answer:
Steps to cellular respiration:
1) In the first step of respiration, glycolysis occurs in which glucose molecule is converted into pyruvate molecule.
2) Krebs cycle is also called citric acidity cycle. In this cycle, hydrogen and electron are produced from the oxidation of pyruvate molecule and provides to electron transport chain.
3) Electrons carried by NADH + H and FADH2 are converted into oxygen through a series of electron carriers, and production of ATP occurs.