Search results
Results from the WOW.Com Content Network
In both males and females, the sex organs consist of two structures: the internal genitalia and the external genitalia. In males, the gonads are the testicles and in females, they are the ovaries . These are the organs that produce gametes (egg and sperm), the reproductive cells that will eventually meet to form the fertilized egg ( zygote ).
Sexual differentiation is the process of development of the sex differences between males and females from an undifferentiated zygote. [1] [2] Sex determination is often distinct from sex differentiation; sex determination is the designation for the development stage towards either male or female, while sex differentiation is the pathway towards the development of the phenotype.
From conception to death, but particularly before adulthood, females are generally less vulnerable than males to developmental difficulties and chronic illnesses. [141] [142] This could be due to females having two x chromosomes instead of just one, [143] or in the reduced exposure to testosterone. [144]
In humans, sex organs or primary sexual characteristics, which are those a person is born with, can be distinguished from secondary sex characteristics, which develop later in life, usually during puberty. The development of both is controlled by sex hormones produced by the body after the initial fetal stage where the presence or absence of ...
The results found by the researches support the notion that gender differences in spatial abilities arose during human evolution such that both sexes cognitively and neurologically developed to behave adaptively. However, the effect of socialization and environment on the difference in spatial ability is still open for debate. [13]
Erections during sleep or when waking up are medically known as nocturnal penile tumescence and colloquially referred to as morning wood. [33] The penis can regularly get erect during sleep and men or males often wake up with an erection. [34] Once a male reaches his teenage years, erections occur much more frequently due to puberty. [35]
The average age that a child reaches sexual maturity differs between the genders: Girls experience puberty between 8 and 13 years old and boys experience it between 9 and 14 years old, according ...
The increased secretion of testosterone from the testes during puberty causes the male secondary sexual characteristics to be manifested. [23] Testosterone directly increases size and mass of muscles, vocal cords, and bones, deepening of the voice, and changing the shape of the face and skeleton. [1]