Question

DNA synthesis can be measured by estimating incorporation of radiolabeled:
(A) Uracil
(B) Ribose sugar
(C) Thymidine
(D) Adenine

Answer 1

Hint: Replication is the process in which DNA strands are synthesised in a semiconservative fashion from previously existing DNA. In radioactivity the strands which are radiolabelled can be easily detected as they glow. Radioactive DNA probes can be used to measure DNA synthesis.

Complete Step by Step Answer:
Each helix that is produced has one strand from the helix it was copied from, DNA replication is semi-conservative. One helix replicates into two daughter helices, each of which has a strand from the original parent helix. By tracking the passage of radioactivity over time using photographic films and emulsions, autoradiography is the study of tagged precursors like 3H. Radioactive substances, such as titrated thymidine, are created by substituting 3H for the thymidine's natural hydrogen (tritium). Because RNA won't be tagged by this, only thymidine is employed for this.

So, "Thymidine" is the right response.

Note: Adenine, guanine, cytosine, and thymine are the nitrogenous bases that make up DNA, while ribose sugar, phosphate molecules, and adenine, guanine, cytosine, and uracil are the nitrogenous bases that make up RNA. As all other nitrogenous bases are comparable in both DNA and RNA, measuring the incorporation of radiolabeled thymine may measure DNA synthesis, while measuring the incorporation of radiolabeled uracil can measure RNA synthesis.