NEET 2021 · Class 12

Biotechnology and its Applications

Now a days it is possible to detect the mutated gene causing cancer by allowing radioactive probe to hybridise its complimentary DNA in a clone of cells, followed by its detection using autoradiography because:

  1. (A)Mutated gene partially appears on a photographic film
  2. (B)Mutated gene completely and clearly appears on a photographic film
  3. (C)Mutated gene does not appear on a photographic film as the probe has no complementarity with it
  4. (D)Mutated gene does not appear on photographic film as the probe has complementarity with it

The NCERT line that answers it

Verbatim line

The clone having the mutated gene will hence not appear on the photographic film, because the probe will not have complementarity with the mutated gene.

Chapter
Biotechnology and its Applications
Section
10.2.3 Molecular Diagnosis
Page
6
Words matched
25 of 25

The answer appears as a continuous sentence in NCERT. This is that sentence.

How this line gives the answer

0, emb=1.0, combined=1.0). Verified: high — The span explicitly states that the mutated gene will not appear on the photographic film because the probe lacks complementarity with it, which directly matches the correct answer's reasoning.

We did this for 1,565 questions.

Every one traced to the exact sentence in NCERT that answers it, including 90% of the 2026 paper. Sit a mock on the real NEET 2027 computer interface and every mark you drop comes back with its line attached.

Take the free 5-minute checkMore from this chapter

Question text is reproduced from the published NEET 2021 paper for study and commentary. NCERT text is quoted, not redistributed; textbooks remain at ncert.nic.in. Our mapping method, including its measured error rates, is published at /methodology.