Carissa Santos Nilani Singler

The Placenta

Description of the Placenta• The placenta is a multipurpose organ! It is

involved in nutrient absorption, waste eradication, and the exchange of gas from the mother’s body supply. To carry out this function, the placenta attaches the developing fetus to the uterine wall.

• The placenta evolves from the shared sperm and egg cells that developed the fetus. It also contains two components:

-the fetal part -the maternal part

Tissue and Anatomy of Placenta

• Before the creation of the placenta, there are six layers of tissue separating both the maternal and fetal blood. Three of these layers are fetal extraembryonic membranes in the chorioallantoic placenta.1.allantoic capillaries lined by endothelium 2.Connective tissue in the form of chorioallantoic

mesoderm 3.Chorionic epithelium - outermost layer of fetal

membranes derived from trophoblasts• The maternal side also has three layers, however the

number of these layers which are preserved - that is those that are not destroyed in the placentation process - varies greatly among species.

• The three potential maternal layers in a placenta are: 1.Endothelium lining endometrial blood vessels 2.Connective tissue of the endometrium 3.Endometrial epithelial cells

• The fetus and the expectant mother are connected by means of the placenta. It provides nourishment while eliminating toxic wastes-those of the mother and baby alike. Its most significant function is to make sure oxygen reaches the baby’s blood supply while allowing Carbon dioxide to be carried away. The umbilical cord aids in this process.

• The placenta protects the fetus from possible infection.• It is only required before the birth process. After the baby is

delivered, the mother must proceed to deliver the “after birth” which includes the placenta. At this point, the placenta becomes obsolete.

• After the placenta is delivered and no longer needed, it can either be disposed of or eaten, depending on your personal views and cultures.

Functions of the Placenta

Functions of the Placenta cont.• The placenta’s endocrine function includes the

production of hormones such as human chronic gonadotropin, otherwise known as hCG, estrogen, progesterone, and other hormones to help maintain the pregnancy which occurs by the end of the second month of pregnancy.

• It also secretes hormones that are significant during pregnancy by the syncytial layer or syncytiotrophoblast of chronic villi.

Friends of the placenta(organ interactions!)• The Placenta interacts with mainly two other organs:1. Umbilical Cord- “life-line” that attaches the placenta

to the fetus. Its made up of three blood vessels: -two smaller arteries- carry blood to the placenta-larger vein- returns blood to fetus.

*The umbilical cord can grow about 60 cm long, which allows the baby an ample amount of cord to safely move around without damaging the cord or the placenta.

2. Uterus- (a.k.a the womb) is the housing for the fetus. -Amniotic sac

ENEMIES!(Diseases) of the placenta• The placenta can be affected

by a number of diseases.• If the placenta implants too

deeply:– Placenta accreta = placenta

attaches too deeply into the uterine wall however it fails to penetrate the uterine muscle

– Placenta previa = placenta grows in the uterus and due to this it covers all or part of the opening to the cervix.

– Placental abruption = the placenta seperates from the uterus wall before the baby is delivered.

Sources• http://www.gynob.com/placenta.htm • http://www.pregnancy-calendars.net/placenta.aspx• http://www.answersingenesis.org/articles/am/v2/n1/placenta• http://en.wikipedia.org/wiki/Placenta#Endocrine_function • http://www.emcom.ca/primer/index.shtml • http://www.vivo.colostate.edu/hbooks/pathphys/reprod/placenta/structure.html• http://www.americanpregnancy.org/pregnancycomplications/

placentaaccreta.html• http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001903/ • http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001902/figure/d19e1452/?

report=objectonly • http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001902/ • http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001902/figure/d19e1454/?

report=objectonly • http://www.healthopedia.com/torch-infections/• http://catalog.nucleusinc.com/generateexhibit.php?ID=1850 • http://www.lucinafoundation.org/pregnancycomplications-placentaaccreta.html• http://www.colorado.edu/intphys/Class/IPHY3430-200/024reproduction.htm• http://www.riversideonline.com/health_reference/Womens-Health/DS00623.cfm