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  2. Human embryonic development - Wikipedia

    en.wikipedia.org/wiki/Human_embryonic_development

    Human embryonic development or human embryogenesis is the development and formation of the human embryo. It is characterised by the processes of cell division and cellular differentiation of the embryo that occurs during the early stages of development. In biological terms, the development of the human body entails growth from a one-celled ...

  3. Maternal physiological changes in pregnancy - Wikipedia

    en.wikipedia.org/wiki/Maternal_physiological...

    During pregnancy the plasma volume increases by 40-50% and the red blood cell volume increases only by 20–30%. [20] These changes occur mostly in the second trimester and prior to 32 weeks gestation. [22] Due to dilution, the net result is a decrease in hematocrit or hemoglobin, which are measures of red blood cell concentration.

  4. Placenta - Wikipedia

    en.wikipedia.org/wiki/Placenta

    Placenta. The placenta (pl.: placentas or placentae) is a temporary embryonic and later fetal organ that begins developing from the blastocyst shortly after implantation. It plays critical roles in facilitating nutrient, gas and waste exchange between the physically separate maternal and fetal circulations, and is an important endocrine organ ...

  5. Gestation - Wikipedia

    en.wikipedia.org/wiki/Gestation

    Gestation. Drawing of a fetus in utero. Gestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). [1] It is typical for mammals, but also occurs for some non-mammals. Mammals during pregnancy can have one or more gestations at the same time, for ...

  6. Fetal circulation - Wikipedia

    en.wikipedia.org/wiki/Fetal_circulation

    The fetal circulatory system includes three shunts to divert blood from undeveloped and partially functioning organs, as well as blood supply to and from the placenta. In humans, the circulatory system is different before and after birth. The fetal circulation is composed of the placenta, umbilical blood vessels encapsulated by the umbilical ...

  7. Heart development - Wikipedia

    en.wikipedia.org/wiki/Heart_development

    Heart development, also known as cardiogenesis, refers to the prenatal development of the heart. This begins with the formation of two endocardial tubes which merge to form the tubular heart, also called the primitive heart tube. The heart is the first functional organ in vertebrate embryos.

  8. Uterus - Wikipedia

    en.wikipedia.org/wiki/Uterus

    Uterus. The uterus (from Latin uterus, pl.: uteri) or womb (/ wuːm /) is the organ in the reproductive system of most female mammals, including humans, that accommodates the embryonic and fetal development of one or more fertilized eggs until birth. [1] The uterus is a hormone -responsive sex organ that contains glands in its lining that ...

  9. Prenatal development - Wikipedia

    en.wikipedia.org/wiki/Prenatal_development

    In human pregnancy, prenatal development is also called antenatal development. The development of the human embryo follows fertilization, and continues as fetal development. By the end of the tenth week of gestational age, the embryo has acquired its basic form and is referred to as a fetus. The next period is that of fetal development where ...