<h3><u>Connective tissue:</u></h3>
It is the layer under the epithelial tissue in the body. It is stronger than epithelial tissue and is found in many organs. It provides protection.
<h3><u>Epithelial tissue:</u></h3>
It covers the outside of the body like a veil. located in the outermost part of the body. Protects the body against microbes and infections.
<h3><u>Muscle tissue:</u></h3>
It is located in the joint areas and forms the support and movement system. It allows us to make bodily movements.
<h3><u>Nervous tissue:</u></h3>
It is the fastest communication tissue. It allows us to feel pain and the sense of touch. It is impossible to repair this tissue after it is damaged. It causes paralysis. It is very important as it plays a role in the activity of neural transmission.
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.
Proteins are a macromolecule and protein contains phosphorus atoms
