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  2. Prenatal development - Wikipedia

    en.wikipedia.org/wiki/Prenatal_development

    Prenatal development (from Latin natalis 'relating to birth') involves the development of the embryo and of the fetus during a viviparous animal's gestation. Prenatal development starts with fertilization , in the germinal stage of embryonic development, and continues in fetal development until birth .

  3. 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.

  4. Development of the human body - Wikipedia

    en.wikipedia.org/wiki/Development_of_the_human_body

    Development before birth, or prenatal development (from Latin natalis 'relating to birth') is the process in which a zygote, and later an embryo, and then a fetus develops during gestation. Prenatal development starts with fertilization and the formation of the zygote , the first stage in embryonic development which continues in fetal ...

  5. Embryo - Wikipedia

    en.wikipedia.org/wiki/Embryo

    Gastrulation is the next phase of embryonic development, and involves the development of two or more layers of cells (germinal layers). Animals that form two layers (such as Cnidaria) are called diploblastic, and those that form three (most other animals, from flatworms to humans) are called triploblastic.

  6. Embryology - Wikipedia

    en.wikipedia.org/wiki/Embryology

    1 - morula, 2 - blastula 1 - blastula, 2 - gastrula with blastopore; orange - ectoderm, red - endoderm. Embryology (from Greek ἔμβρυον, embryon, "the unborn, embryo"; and -λογία, -logia) is the branch of animal biology that studies the prenatal development of gametes (sex cells), fertilization, and development of embryos and fetuses.

  7. Stages of development - Wikipedia

    en.wikipedia.org/wiki/Stages_of_development

    Developmental biology, the study of the process by which animals and plants grow and develop; Prenatal development, also called fetal development, or embryology; Human development (biology), the process of growing to maturity. In biological terms, this entails growth from a one-celled zygote to an adult human being

  8. Prenatal and perinatal psychology - Wikipedia

    en.wikipedia.org/wiki/Prenatal_and_perinatal...

    There are three stages of fetal development. The first stage is the germinal stage begins at conception and is the shortest stage. The second stage is the embryonic stage which begins around the third week of pregnancy and ends at the eighth week. The final stage is the fetal stage which begins at the ninth week of pregnancy and lasts until birth.

  9. 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.