Chapter 12: Conception and Prenatal Development Flashcards
What is the pre-embryonic period?
First 2 weeks after conception
How long can sperm live in the woman’s reproductive tract?
Most 1-2 days
Few up to 80 hours
Four patterns of prenatal growth and development
- cephalocaudal (head to toe)
- central to peripheral
- simple to complex
- general to specific
Decidual layer of placenta that underlies the developing embryo and forms the maternal side of the placenta
decidua basalis
Fertilization age in which skin is translucent
weeks 21-24
In the pre-embryonic period, nutrition to the embryo occurs via ___________
diffusion
Full term gestational age
38-42 weeks
Fertilization age in which implantation is complete
week 2
The secretion of hCG allows the ___________ to secrete estrogen and progesterone until the placenta takes over
corpus luteum
The (fetal, maternal) side of the placenta is rough where it attaches to the uterus
maternal
Fertilization age in which the heart is prominent and reaches the final four-chambered form
week 6
Fertilization age in which the heart is in early development
week 3
During implantation, a small amount of ____________ may occur
bleeding
How is the passage of maternal IgG antibodies beneficial to the fetus?
provides temporary immunity
two functions of progesterone in pregnancy
- changes endometrium into decidua, providing nourishment for early conceptus
- reduces uterine contractions and suppresses maternal reactions to fetal antigens to prevent spontaneous abortion
age since conception
fertilization age
Development of specialized structures is controlled by these three factors
- genetics
- interaction between adjacent tissues
- timing
Term in which fetal movements are felt by the mother
quickening
Fertilization age in which growth continues but growth slows
weeks 33-38
Term for endometrium after implantation
decidua
Term for fertilized ovum
conceptus
Fertilization age in which the embryo has a definite human form with continuing system refinement
week 8
Fertilization age in which the CNS begins to develop
week 3
Nutrition is provided by the _________________ until nidation
conceptus ball
Environmental agents that may cause damage (especially vulnerable during embryonic period)
teratogens
two functions of hCG
- corpus luteum persistence
- secretion of estrogen and progesterone in first 6-8 weeks
The outer cells of the morula create the ___________
blastocyst
Decidual layer of the placenta which lines the remainder of the uterine cavity
decidua parietalis
A low hCG level in a woman who thinks she is pregnant will likely result in ______________. Why?
miscarriage
The corpus luteum will not continue to secrete estrogen and progesterone because the zygote has not secreted enough hCG to maintain a pregnancy.
circulatory shunt that is a hole between the right and left atria
foramen ovale
fraternal twins are termed _____________
dizygotic
Term for largest portion of fallopian tube
ampulla
Fertilization age in which external genitalia begin to differentiate (but not yet distinct)
week 8
Continued development is dependent upon __________
nidation
fatty, cheese-like secretion of fetal sebaceous glands that protects skin from constant exposure to amniotic fluid
vernix caseosa
How do relative fetal and maternal blood carbon dioxide levels allow the fetus to survive in a low-oxygen environment?
More alkaline (more CO2) fetal blood and more acidic (less CO2) maternal blood allows mother’s blood to give up O2 and fetal blood to combine readily with O2
Oogenesis begins during ____________
prenatal life
(Early, Advanced) maternal age at increased risk of multifetal pregnancies
Advanced