Question

question 8 of 10
which of the following explains why a probe will hybridize to a target gene but not to any unrelated genes?
a. the radioactive isotope prohibits hybridization with unrelated genes.
b. the target gene is made of dna, whereas the other genes are made of rna.
c. complementary base pairing occurs only between the probe and the target gene.
d. there is not enough probe for hybridization to occur with more than one gene.

Explanation:

In molecular biology, DNA probes work based on the principle of complementary base pairing. A probe is a single - stranded nucleic acid (usually DNA). It will bind (hybridize) only to a target gene with a complementary sequence. Option A is incorrect because the radioactive isotope is for detection, not for determining specificity. Option B is wrong as genes are typically made of DNA (in most organisms, RNA is not the main form of genes in the context of hybridization probes). Option D is incorrect as the amount of probe is not the determining factor for specificity; it is the base - pairing rules. Complementary base pairing (A - T/U and G - C) ensures that the probe binds only to the target gene with the complementary sequence.

Answer:

C. Complementary base pairing occurs only between the probe and the target gene.