Week 2 Flashcards
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
phototherapy
Involves exposing the neonate to coloured light; blue works best
anoxia
deprivation of oxygen during the birth process and soon after that can result in serious neurological damage within minutes
Apgar scale
neonatal assessment scale with five subtests: Appearance (colour), Pulse (heart rate), Grimace (reflex irritability), Activity (muscle tone) and Respiration (breathing).
0, 1 or 2 on each, max 10 total
Brazelton Neonatal Behavioural Assessment Scale (NBAS).
The NBAS contains 27 items assessing reflexes (such as blinking), physical states (such as irritability and excitability), responses to social stimulation and central nervous system instability (indicated by symptoms such as tremors). Based on these 27 items, the neonate receives an overall rating of ‘worrisome’, ‘normal’ or ‘superior’
Neonates are considered to have low birth weight if they are born weighing less than
2500 grams
preterm
born 3 or more weeks earlier than the optimal 40 weeks after conception
small for date
weigh less than 90% of the average for other neonates who were born at the same gestational age
kangaroo care
mothers or fathers are advised to place their preterm newborns skin-to-skin on their chests for 2–3 hours a day during the early weeks of life
Another reason is that their hearing system is not physiologically mature until they are about 2 years old.
their abilities for sound localisation actually become worse for the first 2 months of life, but then improve rapidly and reach adult levels by 1 year of age
structures of the eye are still immature at birth, specifically: (1) the muscles of the lens, which adjust the eyes’ focus depending on the distance from the object; (2) the cells of the retina, the membrane in the back of the eye that collects visual information and converts it into a form that can be sent to the brain; (3) cones, which identify colours; and (4) the optic nerve, which transmits visual information from the retina to the brain.
Vision improves steadily as their eyes mature, and reaches 20/20 sometime in the second half of the first year.
Their capacity for binocular vision, combining information from both eyes for perceiving depth and motion, is also limited at birth but matures quickly, by about 3–4 months old
Colour vision matures at about the same pace
Neonates can distinguish between red and white but not between white and other colours, probably because the cones are immature
at 4 months same as parents
What benefits of breastfeeding have been demonstrated by scientific research in recent decades?
-Disease protection. Breast milk contains antibodies and other substances that strengthen the baby’s immune system
-Cognitive development. The benefits are mainly for infants who are preterm or low birth weight and consequently are at risk for cognitive difficulties
- Reduced obesity.
-Breastfeeding for at least 6 months reduces the likelihood of obesity in childhood
-Better health in childhood and adulthood: promoting bone density, enhancing vision and improving cardiovascular functioning.
benefits for mothers of breastfeeding
-breastfeeding triggers the release of the hormone oxytocin (reduces bleeding)
-strengthens bones
-Burns weight
-reduces their risk of ovarian and breast cancer even many years later
colostrum
thick, yellowish liquid produced by mammalian mothers during the first days following birth, extremely rich in protein and antibodies that strengthen the baby’s immune system
Three distinct kinds of crying signals have been identified + 2 general ones
Fussing
Anger cry
Pain cry
Basic cry / frustration cry (general)
crying curve
stable for the first 3 weeks of life, rising steadily and reaching a peak by the end of the second month, then declining.
PURPLE
Peak pattern
Unpredictable
Resistant to soothing
Pain-like face
Long lasting
Evening crying
colic
infant crying pattern in which the crying goes on for more than 3 hours a day over more than 3 days at a time for more than 3 weeks
imprinting
instant and enduring bond to the first moving object seen after birth; common in birds
