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What determines male or female sex

Last Updated on March 3, by Julia Wilson. Determining the sex of a cat can be confusing, particularly in young kittens where the anatomy is small and under-developed. Not only that, but a desexed male will look different from an entire male cat. Both will have their scrotum intact; however, the desexed cat will have had his testicles removed, resulting in a small and flat scrotum. The vulva external female genitalia is located underneath the anus and has the appearance of a vertical slit.

XY sex-determination system

XY sex-determination system - Wikipedia

It is important to distinguish between sex and gender. Anatomically, males and females have different reproductive organs: a penis, testicles, and scrotum for males, and a vagina, uterus, and ovaries for females. Other anatomical differences include the development of breasts among females, and the presence of a menstrual cycle. In fact, the majority of male and female biology is identical. Male and female reproductive systems are distinct, but otherwise most bodily systems function the same way. With regards to digestive, respiratory, circulatory, lymphatic, musculoskeletal, nervous, immune, sensory, endocrine, and integumentary systems, males and females have many more similarities than differences.

Sex-determination system

Embryos with XY chromosomes become boys, and those with XX chromosomes become girls. That means that all our sex organs come from the same foundations: The testes in men are equivalent to labia and ovaries in women, and the penis is the equivalent of the clitoris. At around week 7 , the Y chromosome signals for the start of testosterone production, and male genitalia begin to develop. Between 16 and 20 weeks, testosterone levels fall until they reach the range found in early puberty by about 24 weeks. The genital ridge starts lengthening around week 9 to form the penis.
The XY sex-determination system is a sex-determination system used to classify many mammals , including humans , some insects Drosophila , some snakes, some fish guppies , and some plants Ginkgo tree. In this system, the sex of an individual is determined by a pair of sex chromosomes. Females typically have two of the same kind of sex chromosome XX , and are called the homogametic sex.

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Your comments (16)

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