Why some traits occur more in males than in females; name of this phenomenon; and its examples. Introduction: Twenty-three pairs of chromosomes (a total of 46) are present in human DNA. All two pairs of chromosomes carry the same genes (except X and Y chromosomes). The X and Y chromosomes are called sex chromosomes; they determine the sex of human beings. The remaining 22 pairs of chromosomes are termed as autosomes. Females have two homologous X chromosomes, whereas males have one X chromosome and one Y chromosome. Human haploid cells have one set of chromosomes, that is, 23. The egg or sperm cells contain only half of the chromosomes (23 chromosomes). After fertilization, the haploid cells are transferred to the next generation, resulting in the formation of a diploid cell (2n). One set of chromosomes (23) are inherited from the mother to the offspring and another set (23 chromosomes) from the father. If human cells carry 23 pairs of chromosomes, they are known as diploid (2n) cells (somatic cells).

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Chapter 4.4, Problem 10AYLO

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Why some traits occur more in males than in females; name of this phenomenon; and its examples.

Introduction:

Twenty-three pairs of chromosomes (a total of 46) are present in human DNA. All two pairs of chromosomes carry the same genes (except X and Y chromosomes). The X and Y chromosomes are called sex chromosomes; they determine the sex of human beings. The remaining 22 pairs of chromosomes are termed as autosomes. Females have two homologous X chromosomes, whereas males have one X chromosome and one Y chromosome. Human haploid cells have one set of chromosomes, that is, 23. The egg or sperm cells contain only half of the chromosomes (23 chromosomes). After fertilization, the haploid cells are transferred to the next generation, resulting in the formation of a diploid cell (2n). One set of chromosomes (23) are inherited from the mother to the offspring and another set (23 chromosomes) from the father. If human cells carry 23 pairs of chromosomes, they are known as diploid (2n) cells (somatic cells).

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