This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
Aneuploidy is due to: 
Select and explain. 
A. Non-disjunction at meiosis, B. Mosaicism, C. Deletion, D. Translocation
A: Non-disjunction at meiosis
Answer: A: Non-disjunction at meiosis 
Explanation: A i.e. Non disjunction at meiosis- Aneuploidy is a condition in which a cell contains other than haploid number of chromosomes or an exact multiple of it. It produced by non- disjunction of chromosomes at meiosisQ and is common in cancer cells.Term 'Ploid is used to refer number of chromosomes in cells. Euploid: Normal resting diploid cell. Tetraploid: Cells just before division.