Chapter 5 Flashcards
Exam 1
Stages of fetal developement
This period of development extends from the beginning of the third week through the eighth week after conception. Basic structures of all major body organs are completed, structure are most vulnerable to teratogens.
Embryonic Period (Embryo)
The longest part of prenatal development. It begins 9 weeks (end of 8th wk) after conception and ends with birth. All major systems are present in their basic form. Dramatic growth and refinement in the structure and function of all organ systems occur during the fetal period. Teratogens may damage already formed structures but are less likely to cause major structural alterations. The CNS is vulnerable to damaging agents through the entire pregnancy.
Fetal Period/ Stage
What are the functions of the placenta?
*respiration
*production of hormones
*passive immunity
*waste products removal
*acts as a pass through, not a barrier
*2 sided
The key function of the placenta?
respiration
Passage of antibodies from mom to fetus?
passive immunity (mostly occurring in the 3rd trimester)
Mother’s and Baby’s blood ____ _____.
never mix
The placenta is ___ sided
2; maternal and fetal
Hormones produced by the placenta
hCG; Estrogen; Progesterone; Relaxin
Relaxes mother’s pelvis ligaments; can affect other ligaments of the mother (induces waddling)
Relaxin
pregnancy test hormone
hCG
What is formed from the amnion?
umbilical cord
lifeline from the mother to the growing embryo?
umbilical cord
contains one large vein and 2 small arteries
umbilical cord
AVA
2 arteries; 1 vein
In the umbilical cord there are 2 arteries and 1 vein? Which are oxygenated and which are not?
1 large vein (oxygenated)
2 small arteries (deoxygenated)
What surrounds the vein and arteries to prevent compression in the umbilical cord?
Wharton jelly
At term, what is the average length/ width of the umbilical cord?
22 in long and 1 in wide
What is the role of the amniotic fluid?
*helps maintain a constant body temperature for the fetus
*permits symmetric growth and development
*cushions the fetus from trauma
*allows the umbilical cord to be relatively free of compression
*promotes fetal movement to enhance musculoskeletal development
Blood from the placenta to and through the fetus and then back to placenta
fetal circulation
What are the 3 shunts through fetal life span?
Ductus Venosus; Ductus Arteriosus; Foramen Ovale
connects the umbilical vein to the inferior vena cava
Ductus Venosus
connects the main pulmonary artery to the aorta
Ductus Arteriosus
anatomic opening between the right and left atrium
Foramen Ovale
