Sister chromatids have different alleles although carry same genes on same loci. So if it doesn't happen so, like if there are same alleles on sister chromatids then there is a problem in its formation. i.e., male and female alleles haven't contributed equally ( may be an error during their segregation process ). And obviously it doesn't happen in a real cell so we must understand this point. Because normally whenever it happens there's one half from the male and one half from the female. (i.e. maternal and paternal alleles contribute equally).
I hope you get the answer!!!
During meiosis, genetic recombination may occur more than once through the process of cell division, resulting in an increase in genetic variability.
Answer:
I think the answer us sulfuric acid
<span>In sanitary landfills, liquid that is produced by the interaction of rainwater with solid waste is called a leachate. This is because when rainwater makes contact with the solid wastes which are usually buried, the liquid draws out chemical constituents from those wastes. The leachate can then carry harmful substances that can seep through underground and affect groundwater.</span>