placenta
flat vascular organ that aids in nourishing the fetus in the uterus; or attachment for plant seeds
Source: Noland, George B. 1983. General Biology, 11th Edition. St. Louis, MO. C. V. Mosby ...
Placenta
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Placenta
[L. placenta - a small round flat cake] The organ found in the uterus of pregnant mammals (and other viviparous species) composed of maternal and fetal tissues in close contact which provides nourishment and gaseous exchange for the fetus.
The Placenta."The placenta connects the fetus to the uterine wall, and is the organ by means of which the nutritive, respiratory, and excretory functions of the fetus are carried on. It is composed of fetal and maternal portions.
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Placental mammals
In placental mammals, the extraembryonic membranes form a placenta and umbilical cord, which connect the embryo to the mother's uterus in a more elaborate and efficient way.
placenta -- n. In mammals, a tissue formed within the uterus through which nutrients are passed from the mother to the embryo (and later the fetus) and its wastes are removed.
placenta
(pluh-sen-tuh) [Gk. plax, a flat object]
A structure in the pregnant uterus for nourishing a viviparous fetus with the mother's blood supply; formed from the uterine lining and embryonic membranes.
placental mammal ...
placental mammals One of three groups of mammals that carry their young in the mother's body for long periods during which the fetus is nourished by the placenta. Humans are placental mammals.
Placental Mammal a mammal whose young develop within the uterus and gain nutrition via a placenta and umbilical cord
(placenta = a round‚ flat cake) ...
Your Placenta or Mine?
Maternal and embryonic structures interlock to form the placenta, the nourishing boundary between the mother's and embryo's systems.
And the placenta is necessary for the fetus?
For complete development, yes. The very earliest cells are the ones with the most developmental potential.
Placental mammals are everywhere, even in the oceans. A group called cetaceans includes dolphins and whales. They are mammals that evolved and returned to the ocean.
placenta Structure by which an unborn child or animal is attached to its mother's uterine wall and through which it is nourished.
placid Plates on Kinorhyncha.
AKA: placental lactogen
a hormone that promotes maternal breast development during pregnancy.
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z ...
Eutheria: Placental mammals. A subclass of the Class Mammalia (others are monotremes and marsupials). Embryo and fetus are nourished by a placenta.
Blood from the placenta and umbilical cord that are left over after birth is one source of adult stem cells.
The part of the placenta adjacently beneath the chorionic plate; it joins with irregular channels to form the marginal lakes.
Synonym: subchorial lake.
The marsupials and placentals diverged from a pantotheran stem stock in the late Cretaceous. The first marsupials appeared in North America approximately 80 million years ago, e.g.
Alpha-fetoprotein (AFP) -- a protein excreted by the fetus into the amniotic fluid and from there into the mother's bloodstream through the placenta.
Some parts of the blastocyst will form the extra embryonic membranes such as the amnion, chorion and parts of the placenta. The embryo forms on a plate-like layer of cells.
It is now known that stem cells can also be obtained from placenta and amniotic fluids, and pluripotent cells can be derived from adult cells of the skin, blood and other tissues.
Chorionic villus sampling (CVS) A technique used in antenatal diagnosis where a small amount of placental tissue is removed at about 8 - 9 weeks of gestation by transcervical aspiration.
In analyzing more than 10,000 liver and placenta cells of cloned mice, they discovered that about 4% of genes function abnormally.
Chorionic villi sampling is a procedure in which a small amount of the placenta is removed.
For example, the glycoprotein hormone alpha subunit is produced only in certain cell types of the anterior pituitary and placenta, not in lungs or skin; thus expression of the glycoprotein hormone alpha-chain gene is said to be tissue-specific.
To prevent female cells from having twice as many gene products from the X chromosomes as males, one copy of the X chromosome in each female cell is inactivated. In placental mammals, the choice of which X chromosome is inactivated is random, ...
 See also: Human, Organ, Cells, Trans, Embryo
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