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Found Placenta 32 times.

Displaying results 1 to 10.

1. Abruptio placentae
This is the premature separation of the placenta, i.e. separation of the placenta from the site of implantation on the uterus before the delivery of the fetus. It is a life threatening condition for the fetus and occurs about 1 in 500 to 750 deliveries.

2. Alpha fetoprotein (AFP)
This is a protein the blood level of which is measured by laboratory methods. Its level is elevated in the mother's blood when there are fetal spinal cord defects (anencephaly, myelomeningocele), threatened abortion, twin gestation, and abruptio placentae. The AFP screening test for the mother's blood is usually conducted at 16 - 18 weeks of pregnancy. AFP level in the amniotic fluid obtained in amniocentesis is measured to identify abnormal fetal development. In humans, AFP is a useful marker for the diagnosis and assessment of the tumors of the testis (teratocarcinoma and embryonal carcinoma). AFP is also elevated in patients with primary liver cancer (hepatocellular carcinoma) and in women with some types of germ cell ovarian tumors. (Normal range: less than 40 micrograms per liter).

3. Amniotic caruncle
An amniotic caruncle is a small red fleshy swelling of epithelial origin which is occassionally found at the placental insertion of the umbilical cord.

4. Anatropous
Of an ovule , inverted so that the micropyle faces the placenta .

5. Axile
In botany terminology, describes a plant part which is on an axis; of a placenta, on the central axis of the ovary.

6. Beta human chorionic gonadotropin (beta hCG)
This is a glycoprotein composed of two subunits and secreted by the placenta. It is detectable 1 day after implantation of the a fertilized ovum and peaks at 60 to 90 days of gestation. Normal level is less than 5 mIU/mL; 20-100 IU/L 1 to 2 weeks after conception and 50,000 IU/L about 65 days after pregnancy then declines. In molar pregnancy, it can be extremely high initially, (over 100,000 IU/L) but declines with time. Normal Ranges: (in IU/L): non-pregnant: 0 - 5, possibly pregnant: 5 - 25 During Gestation: 0 - 1 wk: 5 - 50, 1 - 2 wks: 50 - 500, 2 - 3 wks: 100 - 1,000, 3 - 4 wks: 500 - 6,000, 1 - 3 months: 5,000 - 200,000, 2nd trimester: 3,000 - 50,000, 3 rd trimester: 1,000 - 50,000 * In the first three weeks of a normal pregnancy, the serum beta hCG approximately doubles every two days. The doubling time of hCG is considered a more reliable method of evaluating an early pregnancy than a single result.

7. Chorion
The chorion is the outermost membrane enclosing the fetus . It is formed from tissues on the outside of the embryo such as the trophoblast , and the part of it attached to the uterus wall eventually develops into the placenta .

8. Chorionic villi sampling (CVS)
A method of prenatal testing in which fetal cells from the fetal side of the placenta (chorionic villi) are extracted and analyzed for chromosomal and biochemical defects.

9. Chorionic villus sampling (CVS)
Taking a biopsy of the placenta , usually at the end of the second month of pregnancy, to test the fetus for genetic abnormalities ( mutation s).

10. Fetal circulation
This is the blood circulation in a fetus . It is distinct from newborn and adult circulation in the following aspects: * in fetal circulation, the cardiac output not only has to perfuse the body, but also the placenta (55% of output goes to the placenta). * the umbilical cord connects the placenta to the fetus, blood from the fetal heart enters the placenta via the umbilical artery * the umbilical vein contains oxygenated blood as versus the artery in newborn or adults containing oxygenated blood. * there are two umbilical arteries and one umbilical vein . * the pressure of the right heart chambers in the fetal circulation is higher than that of the left chambers, as a result, blood from right atrium passes through the foremen ovale to the left atrium, and blood from pulmonary artery passes through the ductus arteriosus to the aorta .


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