Unit 4 Flashcards
(103 cards)
Prenatal Period
The stage of development between conception in birth
Stages of the Prenatal Period
- Germinal
- Embryonic Stage
- Fetal Stage
when does the germinal stage begin
when conception occurs (~ 2 weeks after the deed)
in this stage the “baby” is technically
a zygote
what is a zygote
a single-celled fertilized egg
the germinal stage ends when
the blastocyst implants itself on the uterine wall
what are the 3 crucial support structures after implantation
- amniotic sac
- placenta
- umbilical chord
what does the amniotic sac do
regulates the exchange of fluids, cushions against environmental shocks & temp changes
what does the placenta do
lets oxygen and nutrients get from the parent to the organism
how do teratogens affect the organism
they can harm the organism if they get through the placenta’s semi-permeable membrane
what are teratogens
agents like viruses, chemicals, diseases that can cause harm to the organism
what does the umbilical chord do
it lets blood flow to the embryo/fetus through the placenta
when is the embryonic stage
3rd to 8th week of preggo
what is the organism called in the embryonic stage
embryo
what begins during the embryonic stage
- organogenesis (the development of the major organs)
- sexual differentiation
at which stage of prenatal development do most miscarriages occur
the embryonic stage
what is the 3rd stage of prenatal development called
fetal stage
what portion of the preggo is the fetus stage
2nd month till birth
what is the organism called in this stage
a fetus
what develops in the fetal stage
the development of the brain and senses
what occurs in this stage
rapid growth & maturation of organ system
In the Infant/Child stage what factors tend to affect the development of motor skills/abilities
genes and the environment
in the infant stage when is the growth most rapid
the growth is the most rapid for the 1st 5 years, then is stays pretty stable until puberty
what is the adolescence period
the transition from childhood to adulthood