Question

Match List-I with List-II:
\includegraphics[width=0.6\linewidth]{30.png Choose the correct answer from the options given below:

• (A) - (III), (B) - (IV), (C) - (II), (D) - (I)
• (A) - (III), (B) - (I), (C) - (IV), (D) - (II)
• (A) - (II), (B) - (I), (C) - (IV), (D) - (III)
• (A) - (III), (B) - (IV), (C) - (I), (D) - (II)

Hint:

To remember key genetic model systems:
Griffith/Avery with Streptococcus = DNA is genetic material.
Morgan with Drosophila = Chromosomal theory of inheritance.
Beadle & Tatum with Neurospora = One gene-one enzyme.
Benzer with T4 phage rII locus = Fine structure of the gene.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Pioneering experiments in genetics utilized specific model organisms to demonstrate key principles of inheritance, genetic mapping, and the biochemical nature of genes.

Step 2: Detailed Explanation:
Let us match the model organisms with the genetic principles they helped establish:
1. Streptococcus pneumoniae (A):
Frederick Griffith used this bacterium in his 1928 transformation experiment to show that a "transforming principle" could transfer genetic traits between strains.
In 1944, Avery, MacLeod, and McCarty demonstrated that this transforming principle was DNA, proving that DNA is the genetic material.
Thus, (A) matches with (III).
2. Drosophila melanogaster (B):
Thomas Hunt Morgan and his colleagues used the fruit fly to demonstrate linkage, crossing over, and sex-linkage.
This work confirmed the Chromosomal Theory of Inheritance originally proposed by Sutton and Boveri.
Thus, (B) matches with (I).
3. Neurospora crassa (C):
George Beadle and Edward Tatum exposed this red bread mold to X-rays to induce metabolic mutations.
Their work showed that mutations in specific genes disrupted specific steps in metabolic pathways, leading to the "One gene-one enzyme" hypothesis.
Thus, (C) matches with (IV).
4. T2 bacteriophage rII locus (D):
Seymour Benzer used mutants of the rII locus of bacteriophage T4 to map the fine structure of the gene.
His experiments defined the functional units of genetic material: the cistron (function), recon (recombination), and muton (mutation).
Thus, (D) matches with (II).

Step 3: Final Answer:
The correct matching sequence is (A)-(III), (B)-(I), (C)-(IV), and (D)-(II). This corresponds to option (B).