germinal stage
-0-2 weeks
-cells specialize, 12thday blastocyst implants in uterine tissue
embryonic stage
-week 2-8
-major organs + basic anatomy develop
-gonads develop (w6)
what happens in the 13th and 21st weeks to fetus’s brain
pace of neural formation picks up (neuronal proliferation) and neurons migrate to specific parts of brain, and once there they develop synapses
explain vision capabilities of a fetus
not completely dark but minimal visual stimulus seen, eyelids close until 26th week but sensitive to light weeks 17-20
touch in fetuses
1st sense to develop, displays touch by 32 weeks, first senses touch in perioral (mouth face chin) area
fetuses sense of taste
know fetus can taste all flavors through amniotic fluid and show preferences for certain tastes
smell in fetuses
amniotic fluid takes on odors, an opportunity for odor receptor stimulation, preference for prenatal smell
hearing in fetuses
6 months can hear and create reaction, can memorize sounds (book story), mom’s voice is special, preferences for prenatal sounds
what are the differences in prenatal development according to gender
females grow slower, males more responsive to touch, females more responsive to sounds, females grow faster from prenatal into preteens
what are autosomal disorders caused by?
caused by genes located on chromosomes other than sex chromosomes (autosomes)
what is a trisomy?
condition where child has 3 copies of autosome (typically trisomy 21) (down syndrome) risk of this increases w/ age of mother
what are two other anomalies associated with sex chromosomes
klinefelters syndrome: infidelity, small testicles
turner syndrome, assigned female at birth, heart issues, short, infertile
what is a teratogen?
agents/conditions that can cause congenital abnormalities
what time is most at risk of teratogens?
first 8wk of gestation bc this is when organs develop
how can maternal diseases be teratogens?
rubella, zika, HIV can be transferred to the child during gestation or birth
how can drugs effect the child during gestation?
it is advised not to take any meds, or smoke bc smoking has high premie, stillbirth neonatal, and behavioral disordered babies
what are other harmful influences on prenatal development
inadequate amounts of folic acid and malnutrition, age of mom, maternal chronic illness, maternal mental health
how many genetic mutations do males and females have a chance of passing along?
M passes 55 F passes 14, father can pass teratogens from 2nd hand smoke or workplace, teen and older fathers have been linked to congenital abnormalities
