Week 2 Flashcards
(46 cards)
Teratogen
Behaviour, environment or bodily condition that can have damaging influence on prenatal development
Emryonic phase: Which weeks, and which organs are initially formed in this period?
3-8 weeks, all major organs but sex organs.
Fetal period -
- Which weeks.
- when viability occurs, and why.
- What occurs at 28 weeks
-Week 9 to birth
-Rare before the third trimester, because of the immaturity of lungs
-sleep-wake cycle similar to newborn, can remember and respond to sound, taste and mother’s movements
Heritability
An estimate of the extent to which genes are responsible for the differences among people within a specific population. The value of the heritability estimate ranges from 0 to 1.00. The higher the heritability, the more the characteristic is believed to be influenced by genetics.
Do Heritability estimates measure pheno or genotype?
Phenotype
concordance rate
degree of similarity in phenotype among pairs of family members, expressed as a percentage
epigenesis
development results from the bidirectional interactions between genotype and environment
reaction range
range of possible developmental paths established by genes; environment determines where development takes place within that range
theory of genotype → environment effects (def + 3 types)
theory proposing that genes influence the kind of environment we experience
passive genotype → environment effects
Evocative genotype → environment effects
Active genotype → environment effects
passive genotype → environment effects
the type that results from the fact that in a biological family, parents provide both genes and environment to their children
evocative genotype → environment effects
the type that results when a person’s inherited characteristics evoke responses from others in the environment
active genotype → environment effects
the type that results when people seek out environments that correspond to their genotypic characteristics
key to preventing anencephaly and spina bifida
Folic acid
important for building the blood supply of mother and fetus:
Iron
_____ is crucial because low-_____ intake during pregnancy increases the risks of miscarriage, stillbirth and abnormalities in fetal brain development.
Iodine
fetal alcohol spectrum disorder (FASD)
set of problems that occur as a consequence of high maternal alcohol use during pregnancy, including facial deformities, heart problems, misshapen limbs and a variety of cognitive problems
Multifactorial disorders
involve a combination of genetic and environmental factors
In __________, a long hollow needle is inserted into the pregnant woman’s abdomen and, using the ultrasound image for guidance, a sample of the amniotic fluid is withdrawn from the placenta surrounding the fetus. 15-20 weeks.
amniocentesis
chorionic villus sampling (CVS)
entails sampling and analysing cells early in development to detect possible genetic problem (5-10 weeks)
a tube is inserted through the vagina and into the uterus to obtain the cell sample. CVS entails a slight but genuine risk of miscarriage or damage to the fetus, so it is used only when there is a family history of genetic abnormalities or the woman is age 35 or over
99% accurate
Non-invasive prenatal testing (NIPT)
A method called non-invasive prenatal testing (or cell-free DNA analysis) was first introduced in 2013 in Australia and is nearly risk-free; mothers only give a simple blood sample.
There is evidence that the test is 99% accurate in detecting chromosomal abnormalities like Down syndrome and it is far less likely to get false positives than the procedures described above
intrauterine insemination (IUI)
which involves injecting the man’s sperm directly into the woman’s uterus, timed to coincide with her ovulation
If the primary problem is that the woman cannot ovulate properly, the most common approach is to stimulate ovulation through…
fertility drugs
in vitro fertilisation (IVF).
In IVF, after fertility drugs are used to stimulate the growth of numerous follicles in the woman’s ovaries, the ripe ova are then removed and combined with the man’s sperm so that fertilisation will take place.
After a few days, it is possible to tell which of the zygotes have developed and which have not, so the most promising two or three are placed into the woman’s uterus in the hope that one will continue to develop. In vitro fertilisation success rates have steadily improved in recent years, and are currently about 50% per attempt for women under age 35
neonatal jaundice
yellowish pallor common in the first few days of life due to immaturity of the liver
