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Of the two diploid species, species I has 36 chromosomes and species II has 28 chromosomes. How many chromosomes would be found in an allotriploid individual?
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- 42 or 54
- 46 or 50
- 74 or 86
- 84 or 108
Correct Option: B
Given, Species I has 36 (2n = 36) chromosomes and species II has 28 (2n = 28) chromosomes. Now, species I and II are
crossed to obtain an allotriploid individual. That means it has a total chromosome of 3n. When the two diploid species are crossed, the chromosome set of one species would not undergo reduction division for the purpose of obtaining the allotriploid hybrid. That means the 3n would be contributed by 2n and n. So, the 2n can be from species I or II and so the n can be from species II or I respectively. Hence, the required chromosome number would be :
Species I (2n) + Species II (n) = 3n
⇒ 36 + 14 = 50
Or Species I (n) + Species II (2n) = 3n
⇒ 18 + 28 = 46
