GENETICS AND EVOLUTION
GENETIC BASIS OF INHERITANCE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Only X chromosome
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Only Y chromosome
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Either X or Y chromosome
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Either XX or XY chromosomes
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Detailed explanation-1: -Normal human spermatozoa carry either the X or the Y chromosome. The differences between X and Y spermatozoa (X and Y haploid cells) may exist in two areas: the different chromosomes (i.e. different kinds and numbers of genes) and the different sperm structures and functions (i.e. different genetic expression).
Detailed explanation-2: -A spermatozoon is a male germ cell capable of fertilizing an oocyte and carries genetic information for determining the sex of the offspring. It comprises autosomes and an X (X spermatozoa) or a Y chromosome (Y spermatozoa).
Detailed explanation-3: -Humans and most mammals have two sex chromosomes, the X and Y. Females have two X chromosomes in their cells, while males have X and Y chromosomes in their cells. Egg cells all contain an X chromosome, while sperm cells contain an X or a Y chromosome.
Detailed explanation-4: -At present, laboratory methods that can successfully differentiate X-from Y-bearing sperm do exist; namely, staining with quinacrine mustard and DNA flow cytometry.