You have to start with low power, move to medium and then go to high. You have to be careful and use fine focus to make sure you don’t scratch the slide or the lens
Al-Qaeda <span>chose its first American bombing targets if t</span>he targets were in Africa, which is not far from the Middle East. The second one is your answer. I hope this is the answer that you are looking for and it comes to your help.
For the environmental risk, it is much better to prevent pollution than to deal with it after it has already been made. When you deal with the pollution, it is hard to say that you can eliminate completely. So, prevention is the first strategy.
Answer:
true
Explanation:
DNA synthesis is performed by the enzyme DNA polymerase. However, DNA polymerase requires the presence of a free 3' OH on the existing DNA or RNA segment. The enzyme primase forms small RNA segments that serve as primers. Primers are formed by using the DNA template strands and have free 3' OH ends. DNA polymerase extends the primers by adding deoxyribonucleotides according to the sequence of the DNA template strand. Therefore, DNA polymerases are the enzymes of primer elongation.
Answer:
a. True, b. False, c.True, d. True
Explanation:
a. Base excision repair is started by a DNA glycosylase that recognizes the changes and removes the altered base by cleavage of the glycosidic bond binding the base and the deoxyribose sugar together.
b. Nucleotide excision repair works by a cut-and patch mechanism that removes their heavy lesions, including pyrimidine dimers and nucleotides . Endonucleases are responsible for the lesion of the damaged strand.
c. Nucleotide excision repair is initiated by the proteins namely UvrA, UvrC, and UvrB in Escherichia coli.
-UvrD (helicase II) later removes the damaged strand
-DNA polymerase I (PolI) fills in the resulting gap.
d. DNA glycolases removes the damaged nitrogenous base.
-It leaves the sugar-phosphate backbone intact and thus creating an apurinic/apyrimidinic site, which is commonly referred to as an AP site.
e. Xeroderma pigmentosum complementation group A(XPA)
-This is an essential protein in the nucleotide excision repair pathway.
- It helps to make a pre-incision complex along with other proteins.
