Biology, 26.11.2019 21:31, breanastone14

Non-disjunction involving the x-chromosome may occur during oogenesis and produce two kinds of eggs. if normal sperm fertilize these two types, which of the following pairs of genotypes are possible?

a. xx and xy
b. xxy and xo
c. xyy and xo
d. xyy and yo

Answers: 1

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Answers

answered: leilaford2003

The correct answer will be option-B

Explanation:

Non-disjunction is the process of the failure of the separation of the homologous chromosomes during cell division which could be observed during the meiosis I, meiosis II or mitosis.

If Non-disjunction takes place during the oogenesis then the resultant cells will be formed with XX and O gametes.

When a normal male sperm with XY fertilizes the cells then they will form four combinations:

1. XX + X = XXX

2. XX + Y = XXY

3. O + X = XO

4. O + Y = YO

Thus, in the given question option-B is the correct answer.

answered: Guest

image result for describe the various types of gene mutationsghr.nlm.nih.gov

the types of mutations include: missense mutation: this type of mutation is a change in one dna base pair that results in the substitution of one amino acid for another in the protein made by a gene. nonsense mutation: a nonsense mutation is also a change in one dna base pair.

explanation:

answered: Guest

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