A nuclease (also archaically known as nucleodepolymerase or polynucleotidase) is an enzyme capable of cleaving the phosphodiester bonds between nucleotides of nucleic acids. Nucleases variously effect single and double stranded breaks in their target molecules. In living organisms, they are essential machinery for many aspects of DNA repair. Defects in certain nucleases can cause genetic instability or immunodeficiency.[1] Nucleases are also extensively used in molecular cloning.[2]
Depiction of the restriction enzyme (endonuclease) HindIII cleaving a double-stranded DNA molecule at a valid restriction site (5'–A|AGCTT–3').
There are two primary classifications based on the locus of activity. Exonucleases digest nucleic acids from the ends. Endonucleases act on regions in the middle of target molecules. They are further subcategorized as deoxyribonucleases and ribonucleases. The former acts on DNA, the latter on RNA.[2]
Answer:
The bulging eyes of most frogs allow them to see in front, to the sides, and partially behind them. The eyes help push the food down its throat. Eyes positioned atop the head give frogs a field of vision of almost 180 degrees. This peripheral vision helps them spot predators and prey.
Explanation:
Answer:
a. Odds ratio = 1.58
b. Inasmuch the odds ratio is greater than 1, this means that higher odds of melanoma exist in people exposed to indoor tanning, than in those not exposed to indoor tanning
Explanation:
For case study
Let 'a' represent the total population of people with melanomia = 696
Let 'b' represent the total number of people with melanomia exposed to indoor tanning = 1107 – 696 = 411 people
For control study
Let 'c' represent the total population = 1500
Let 'd' represent the total number of people not exposed to indoor tanning = 1500 - (0.428 * 1500)
= 1500 - 723
Total number of people not exposed to indoor tanning = 777 people
a. Odds ratio = (a/b) / (d/c) = (696/411) / (777/723)
= 1.69 / 1.07 = 1.58
b. Inasmuch the odds ratio is greater than 1, this means that higher odds of melanoma exist in people exposed to indoor tanning, than in those not exposed to indoor tanning.