Match Column 1 with Column 2:
| COLUMN 1 | COLUMN 2 |
| A. Gregor J. Mendel | i. Chromosomal theory of inheritance |
| B. Sutton and Boveri | ii. Laws of inheritance |
| C. Henking | iii. Drosophila |
| D. Morgan | iv. Discovered X body |
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → A-ii, B-i, C-iv, D-iii
(A) Gregor J. Mendel — this matches (ii) Laws of inheritance. He carried out hybridisation experiments on garden peas for seven years and proposed the laws of inheritance.
(B) Sutton and Boveri — this matches (i) Chromosomal theory of inheritance. They linked the pairing and separation of chromosomes with the segregation of Mendel’s factors.
(C) Henking — this matches (iv) Discovered X body. In 1891 he traced a nuclear structure through spermatogenesis in insects and named it the X body; it was later found to be a chromosome.
(D) Morgan — this matches (iii) Drosophila. Thomas Hunt Morgan tested the chromosomal theory using the fruit fly Drosophila melanogaster.
NCERT Extract:
Mendel’s Laws of Inheritance – “… Gregor Mendel, conducted hybridisation experiments on garden peas for seven years (1856-1863) and proposed the laws of inheritance in living organisms.”
Chromosomal Theory of Inheritance – “… Sutton and Boveri argued that the pairing and separation of a pair of chromosomes would lead to the segregation of a pair of factors they carried. Sutton united the knowledge of chromosomal segregation with Mendelian principles and called it the chromosomal theory of inheritance. … Morgan worked with the tiny fruit flies, Drosophila melanogaster (Figure 4.10), which were found very suitable for such studies.”
Sex Determination – “… Henking (1891) could trace a specific nuclear structure all through spermatogenesis in a few insects, and it was also observed by him that 50 per cent of the sperm received this structure after spermatogenesis, whereas the other 50 per cent sperm did not receive it. Henking gave a name to this structure as the X body but he could not explain its significance.”