When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Human fertilization - Wikipedia

    en.wikipedia.org/wiki/Human_fertilization

    Human fertilization is the union of an egg and sperm, occurring primarily in the ampulla of the fallopian tube. [1] The result of this union leads to the production of a fertilized egg called a zygote, initiating embryonic development. Scientists discovered the dynamics of human fertilization in the 19th century. [2]

  3. Sexual differentiation in humans - Wikipedia

    en.wikipedia.org/wiki/Sexual_differentiation_in...

    Most mammals, including humans, have an XY sex-determination system: the Y chromosome carries factors responsible for triggering male development. In the absence of a Y chromosome, the fetus will undergo female development. This is because of the presence of the sex-determining region of the Y chromosome, also known as the SRY gene. [5]

  4. Human embryonic development - Wikipedia

    en.wikipedia.org/wiki/Human_embryonic_development

    Human embryology is the study of this development during the first eight weeks after fertilization. The normal period of gestation (pregnancy) is about nine months or 36 weeks. The germinal stage refers to the time from fertilization through the development of the early embryo until implantation is completed in the uterus .

  5. Top US health agency updates definitions of female and male ...

    www.aol.com/news/top-us-health-agency-updates...

    "The sex of a human, female or male, is determined genetically at conception (fertilization), and is observable before birth," according to the guidance.

  6. Human reproduction - Wikipedia

    en.wikipedia.org/wiki/Human_reproduction

    Human sexual reproduction, to produce offspring, begins with fertilization. Successful reproduction typically involves sexual intercourse between a healthy, sexually mature and fertile male and female. [1] During sexual intercourse, sperm cells are ejaculated into the vagina through the penis, resulting in fertilization of an ovum to form a ...

  7. Sexual differentiation - Wikipedia

    en.wikipedia.org/wiki/Sexual_differentiation

    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.

  8. Sex differences in human physiology - Wikipedia

    en.wikipedia.org/wiki/Sex_differences_in_human...

    The pelvis is, in general, different between the human female and male skeleton. [14] [15] Although variations exist and there may be a degree of overlap between typically male or female traits, [14] [15] the pelvis is the most dimorphic bone of the human skeleton and is therefore likely to be accurate when using it to ascertain a person's sex ...

  9. Female reproductive system - Wikipedia

    en.wikipedia.org/wiki/Female_reproductive_system

    The human female reproductive system is made up of the internal and external sex organs that function in the reproduction of new offspring. The reproductive system is immature at birth and develops at puberty to be able to release matured ova from the ovaries , facilitate their fertilization , and create a protective environment for the ...