An abnormal human baby with 'XXX' sex chromosomes was born due to:
Correct answer: D. Formation of abnormal ova in the mother.
- A. Fusion of two ova and one sperm
- B. Fusion of two sperms and one ovum
- C. Formation of abnormal sperms in the father
- D. Formation of abnormal ova in the mother.
Explanation
XXX usually results from maternal nondisjunction producing an XX ovum fertilized by an X sperm - a maternal meiotic error.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? [email protected]
About Inheritance
Mendel's laws explain segregation, independent assortment and the prediction of genetic ratios using alleles, genotypes and phenotypes. The chapter also covers linked genes, recombination and crossing over during meiosis, then applies pedigree reasoning to X-linked recessive traits, which show different inheritance patterns in males and females.
Practise Inheritance
1,245 free Inheritance MCQs from Biology, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Biology questions like this
Biology is on 8 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Inheritance questions
Alleles are:
What is the term for the different forms of a gene that occupy the same position on a chromosome?
The term "linkage" was coined by:
A man whose father was color blind marries a woman who had a color-blind mother and normal father. What percentage of male children of this couple will be color blind?
Which stage of meiosis introduces the maximum genetic variation?
The condition in which both alleles of a gene are expressed equally in heterozygotes is called: