本题目来源于试卷: Continuity and Change D.8 Inheritance,类别为 IB生物学
[单选题]
Neurons of the fruit flddosx re6u9avh6t eq v0/1+a*y (Drosophila met 8 pzln1h9s6:kk m0nilanogaster) have 8 chromosomes. How many chromosomes are in a fertilised oocyte of a fruit n ks:ik81m60lzt9p n hfly?
A. 8
B. 4
C. 2
D. 16
参考答案: A
本题详细解析:
At fertilisation, two gametes, which are haploid, fuse together to produce a diploid cell. Gametes of a fruit fly have a haploid number of 4, so fertilisation produces a cell with 8 chromosomes (choice A). Choice B is incorrect because 4 is the haploid number. Choice C is incorrect because fruit fly somatic cells have 8 chromosomes and fertilised egg cells have 8 chromosomes. Choice D is incorrect because 16 is twice the diploid number of fruit flies.
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