Genetics help?

4. Zebras and donkeys are closely related, diploid species of the Equus genus. A certain species of zebra that has 46 chromosomes per cell mates with a donkey that has 62 chromosomes per cell. This can result in an alloploid offspring, referred to as a “zebroid” in this case.

a. How many chromosomes should this hybrid offspring inherit in total from its parents? 

b. What if one of the parents contributed a nullisomic gamete to this offspring? Yes or no, is there a different number of total chromosomes expected in this alloploid whether the zebra parent or the donkey parent had done so?

c. What if one of the parents contributed a disomic gamete to this offspring? Yes or no, is there a different number of total chromosomes expected in this alloploid whether the zebra parent or the donkey parent had done so?

d. What if one of the parents contributed a diploid gamete to this offspring? Yes or no, is there a different number of total chromosomes expected in this alloploid whether the zebra parent or the donkey parent had done so?

e. Although the offspring would not be viable, consider that the developing zebroid is an allotriploid. What are the possible total number of chromosomes this offspring could have inherited?

1 Answer

Relevance
  • 1 month ago

    a. The gametes from the two parents would have 23 and 31 chromosomes. So, the zebroid would have: 23 + 31 = 54 chromosomes

    b. No, the offspring would, in this case, have 53 chromosomes

    c. Again, it wouldn't matter. The offspring would have 55 chromosomes

    d. Here, it would make a big difference. The offspring would have an additional 23 or 31 chromosomes

    e. It would have either 46+31 = 77 or 23+62 = 85 chromosomes, depending on which parent provided a diploid number.

Still have questions? Get answers by asking now.