Q.4 Match List-I with List-II
| List-I (Organism) | List-II (Number of Chromosome) |
|---|---|
| (A) Fruit fly (Drosophila melanogaster) | (I) Diploid number 40 |
| (B) Nematode (Caenorhabditis elegans) | (II) Haploid number 06 |
| (C) Human (Homo sapiens) | (III) Haploid number 23 |
| (D) Mouse (Mus musculus) | (IV) Diploid number 08 |
Choose the correct answer from the options given below:
1. (A) – (I), (B) – (II), (C) – (III), (D) – (IV)
2. (A) – (II), (B) – (IV), (C) – (III), (D) – (I)
3. (A) – (IV), (B) – (II), (C) – (III), (D) – (I)
4. (A) – (I), (B) – (IV), (C) – (III), (D) – (II)
Fruit fly (Drosophila melanogaster) has a diploid chromosome number of 8, nematode (Caenorhabditis elegans) has a haploid number of 6, human (Homo sapiens) has a haploid number of 23, and mouse (Mus musculus) has a diploid number of 40. The correct matching is option 3: (A)-(IV), (B)-(II), (C)-(III), (D)-(I).
Chromosome Details
These model organisms in genetics have distinct chromosome counts vital for exams like GATE Life Sciences.
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Fruit fly: Diploid 2n=8 (4 pairs), matches (IV).
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Nematode: Haploid n=6 (diploid 12), matches (II).
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Human: Haploid n=23 (diploid 46), matches (III).
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Mouse: Diploid 2n=40, matches (I).
Option Analysis
Option 1: (A)-(I), (B)-(II), (C)-(III), (D)-(IV)
Wrong. (A) mismatches—fruit fly is not diploid 40 (mouse).
Option 2: (A)-(II), (B)-(IV), (C)-(III), (D)-(I)
Wrong. (A) haploid 6 is nematode, not fruit fly; (B) diploid 8 is fruit fly.
Option 3: (A)-(IV), (B)-(II), (C)-(III), (D)-(I)
Correct. All match: fruit fly diploid 8, nematode haploid 6, human haploid 23, mouse diploid 40.
Option 4: (A)-(I), (B)-(IV), (C)-(III), (D)-(II)
Wrong. (A) diploid 40 is mouse; (B) diploid 8 is fruit fly.
Fruit fly chromosome number is a key topic in genetics for competitive exams like GATE Life Sciences. This PYQ matches organisms—fruit fly (Drosophila melanogaster), nematode (Caenorhabditis elegans), human (Homo sapiens), and mouse (Mus musculus)—with their chromosome counts: diploid 40 (I), haploid 6 (II), haploid 23 (III), diploid 8 (IV).
Why Chromosome Numbers Matter
Fruit fly chromosome number (diploid 8) makes it ideal for genetic studies due to visible mutations in few pairs. Nematode’s haploid 6 simplifies mapping; human haploid 23 defines gametes; mouse diploid 40 aids mammal research.
| Organism | Correct Match | Number Type | Value |
|---|---|---|---|
| Fruit fly (Drosophila) | (IV) | Diploid | 8 |
| Nematode (C. elegans) | (II) | Haploid | 6 |
| Human (H. sapiens) | (III) | Haploid | 23 |
| Mouse (M. musculus) | (I) | Diploid | 40 |
Exam-Tip Solution
Option 3 is correct: (A)-(IV), (B)-(II), (C)-(III), (D)-(I). Memorize haploid vs. diploid distinctions for quick matching in MCQs.
