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 ).
The process of meiosis in females occurs during oogenesis, and differs from the typical meiosis in that it features a long period of meiotic arrest known as the dictyate stage and lacks the assistance of centrosomes. [53] [54] In males, meiosis occurs during spermatogenesis in the seminiferous tubules of the testicles.
The mutation frequencies for cells throughout the different stages of spermatogenesis in mice is similar to that in female germline cells, that is 5 to 10-fold lower than the mutation frequency in somatic cells [19] [13] Thus low mutation frequency is a feature of germline cells in both sexes.
Structural and/or genetic dissimilarity (due to hybridization or mutation) between the pseudoautosomal regions of the X and Y chromosomes can disrupt pairing and recombination, and consequently cause male infertility. The SHOX gene in the PAR1 region is the gene most commonly associated with and well understood with regards to disorders in ...
The human brain. Differences in male and female brain size are relative to body size. [83] Early research into the differences between male and female brains showed that male brains are, on average, larger than female brains. This research was frequently cited to support the assertion that women are less intelligent than men.
The Y chromosome is one of two sex chromosomes in therian mammals and other organisms.Along with the X chromosome, it is part of the XY sex-determination system, in which the Y is the sex-determining chromosome because the presence of the Y chromosome causes offspring produced in sexual reproduction to be of male sex.
During meiosis in sexual organisms (sexual reproduction), two homologous chromosomes cross over one another and exchange genetic material. This random process of exchanging genetic material is known as recombination, and it is governed by its own set of genes. [3] Being controlled by genes means that recombination is variable in frequency.
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.