"Water quality" may include the amounts of dissolved oxygen
and the levels of algal growth, pollutants which may be present and the pH level. Water quality effects also which types of organisms can
survive in a body of water.
Shellfish require a high level
of dissolved oxygen and their abundance is an indication of good water quality. Shellfish are sensitive to changes in the ecosystem and they cannot easily escape changes in the water quality. These are one of the reasons why shellfish are good indicators of water quality.
This would indicate that the most accurate diagnosis of your condition would be sickle cell disease.
Sickle cell disease is a condition that affects hemoglobin; the iron containing molecule in red blood cells that transport oxygen from the lungs to the rest of the body. This condition causes the red blood cells to become misshapen or deform into an abnormal crescent shape which can easily get accumulated together and block off small blood vessels. The blocking of the blood vessels will prevent blood from flowing to where it should in the body and this can result to pain and organ damage in affected persons.
Answer: The tension is relieved by an enzyme named topoisomerase
Explanation:
As replication starts DNA polymerase needs to move forward of double strand DNA, this creates a lot of tension in the DNA molecule. The tension is relieved by the action of an enzyme named topoisomerase. The stress relieve is needed for the progresion of the replication mechanism.
There are to types of topoisomerases:
a) Topoisomerase I
b) Topoisomerase II
Topoisomerase I underwinds the DNA double helix by making a single cut in one of the strands of the DNA molecule. Once the cut is made, the DNA unwinds and torsional stress is released. Finally the DNA strand , that was cut is ligated ( see attached image)
Topoisomerase II acts when torsional stress is made because two DNA strands cross each other (superhelical stress). Topoisomerase II cuts both strands of a DNA molecule. After this cut is made the DNA unwinds and torsiona stress is relieved ). Finally both DNA strands are ligated ) see attached image)
Topoisomerases II enzymes require ATP hydrolysis to perform the cut of both of the DNA strands.