Search results
Results from the WOW.Com Content Network
The form of the human placenta is generally classified as a discoid placenta. Within this, the cotyledons are the approximately 15-25 separations of the decidua basalis of the placenta, separated by placental septa. [3] Each cotyledon consists of a main stem of a chorionic villus as well as its branches and sub-branches. [3]
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, producing hormones that regulate both maternal and fetal ...
The part of the ovary where the funiculus attaches is referred to as the placenta. In botany, the term placentation most commonly refers to the arrangement of ovules inside an ovary. Placentation types include: Basal: The placenta is found in mono to multi carpellary, syncarpous ovary. Usually a single ovule is attached at the base (bottom).
The fetal circulation is composed of the placenta, umbilical blood vessels encapsulated by the umbilical cord, heart and systemic blood vessels. A major difference between the fetal circulation and postnatal circulation is that the lungs are not used during the fetal stage resulting in the presence of shunts to move oxygenated blood and ...
The placenta also produces human placental lactogen (hPL), which stimulates maternal lipolysis and fatty acid metabolism. As a result, this conserves blood glucose for use by the fetus. It can also decrease maternal tissue sensitivity to insulin, resulting in gestational diabetes.
A human fetus, attached to placenta, at three months gestational age In humans, the fetal stage starts nine weeks after fertilization. [ 7 ] At this time the fetus is typically about 30 millimetres ( 1 + 1 ⁄ 4 in) in length from crown to rump , and weighs about 8 grams. [ 7 ]
The placenta attaches to the wall of the uterus, and the fetus' umbilical cord develops from the placenta. These organs connect the mother and the fetus. Placentas are a defining characteristic of placental mammals, but are also found in marsupials and some non-mammals with varying levels of development. [6]
This is an accepted version of this page This is the latest accepted revision, reviewed on 6 January 2025. Procreative biological processes of humanity Part of a series on Sex Biological terms Sexual dimorphism Sexual differentiation Feminization Virilization Sex-determination system XY XO ZW ZO Temperature-dependent Haplodiploidy Heterogametic sex Homogametic sex Sex chromosome X chromosome Y ...