The Prenatal Period: aspects such as cell division, sex, genetic abnormalities, and
dominance.
The Prenatal Stages: the germinal, embryonic, and fetal (foetal) periods
Prenatal Environmental Stages: age if parents, nutrition, emotional stages, and substance
abuse
The Birth Process: complications of childbirth
Prenatal Stages
#The prenatal period is the period
from conception to birth and lasts 9
months.
# 280 days of pregnancy
# THREE STAGES
1. The Germinal Stage
o The germinal stage is called the period of zygote, beginning with
conception and lasts 1-2 weeks.
o Characterized mainly by the growth of zygote and beginning of
physiologically dependent relationship between zygote & support
system of mother
o Mitosis begins within 24-36 hours after conception when Z enters cell
division/cleavage
o Develops 2 into 4… in 32
o Billions of specialized cells
o 4 days : 60-70 cells developed
o While cell division takes place = cell mass travel along fallopian tube
and reaches uterus after 5 days
o Z attaches itself to wall of uterus
o Implantation end of this stage
2. The Embryonic Stage
o From implantation to 8 weeks and the development of the organism is
called the embryo
o It develops into three layers
1: Ectoderm (outer layer) mainly hair, nails, teeth, sensory organs, and
nervous system develop
2: Mesoderm (middle layer) mainly muscles, skeletons, inside layer of
skin, excretory system and blood circulation develops
3: Endoderm (inside layer) mainly digestive system, liver, pancreas,
sweat gland and respiratory system develops
, Umbilical Cord: “lifeline” Placenta is a structure
connecting embryo to that grows on inner
placenta. Oxygen + wall of uterus and
nutrients from mother suppliers the NO and
pass through this to E removes waste
3RD Week: blood vessels + stomach begin to develop, and a small tube (later
becomes the heart) begins to beat at end of 4th week
Embryo is 0.5cm long and the heart and brain become more clearly differentiated.
Only rudimentary of body system. Can’t distinguish between human/rabbit/elephant.
4th-6th Week: expected menstruation doesn’t take place + tests are positive
Now experience nausea with frequent urination
5th Week: brain & heart function needed more than digestive system, upper part of
body develops before the lower part of the body
Brain expands and generates more that 250 000 neurons per minute. Formation of
complete chest and abdomen.
Eyes recognized behind closed eyelids, lung buds begin to develop, plates for hands
and feet begin to appear + olfactory lobe (smell) begins to develop.
6th Week: heart undergoes NB structural + functional changes. Tube-like shape
changes into heart with 4 chambers . (11-14mm long) day 36 arm buds visible.
8th Week: 30mm long where the face, mouth, eyes and ears are distinguished.
Stumpy fingers + toes appear
At this stage, sexual organs are developed, muscles and cartilage have developed
BUT clear neuromotor activity is absent.
INTERNAL ORGANS begin to fulfil their function with producing red blood cells &
stomach producing digestive juices.
3. The Fetal Stage
o The developing organism is known as a fetus
o Further differentiation now takes place so organs/systems can function
effectively
o During 3rd month – the penis + scrotum of male fetus and the labia of female
fetus appears.
o Male organs develop faster
o A connection between nervous system and muscles with spontaneous
movement
o Don’t feel movement until 4th month (now feels movements)
o During 4th month – face becomes more human, and body starts to lengthen.
o Heart beats between 120-160 times a minute
o Activities include thumb sucking , hiccupping, and all reflexes found in
newborns
dominance.
The Prenatal Stages: the germinal, embryonic, and fetal (foetal) periods
Prenatal Environmental Stages: age if parents, nutrition, emotional stages, and substance
abuse
The Birth Process: complications of childbirth
Prenatal Stages
#The prenatal period is the period
from conception to birth and lasts 9
months.
# 280 days of pregnancy
# THREE STAGES
1. The Germinal Stage
o The germinal stage is called the period of zygote, beginning with
conception and lasts 1-2 weeks.
o Characterized mainly by the growth of zygote and beginning of
physiologically dependent relationship between zygote & support
system of mother
o Mitosis begins within 24-36 hours after conception when Z enters cell
division/cleavage
o Develops 2 into 4… in 32
o Billions of specialized cells
o 4 days : 60-70 cells developed
o While cell division takes place = cell mass travel along fallopian tube
and reaches uterus after 5 days
o Z attaches itself to wall of uterus
o Implantation end of this stage
2. The Embryonic Stage
o From implantation to 8 weeks and the development of the organism is
called the embryo
o It develops into three layers
1: Ectoderm (outer layer) mainly hair, nails, teeth, sensory organs, and
nervous system develop
2: Mesoderm (middle layer) mainly muscles, skeletons, inside layer of
skin, excretory system and blood circulation develops
3: Endoderm (inside layer) mainly digestive system, liver, pancreas,
sweat gland and respiratory system develops
, Umbilical Cord: “lifeline” Placenta is a structure
connecting embryo to that grows on inner
placenta. Oxygen + wall of uterus and
nutrients from mother suppliers the NO and
pass through this to E removes waste
3RD Week: blood vessels + stomach begin to develop, and a small tube (later
becomes the heart) begins to beat at end of 4th week
Embryo is 0.5cm long and the heart and brain become more clearly differentiated.
Only rudimentary of body system. Can’t distinguish between human/rabbit/elephant.
4th-6th Week: expected menstruation doesn’t take place + tests are positive
Now experience nausea with frequent urination
5th Week: brain & heart function needed more than digestive system, upper part of
body develops before the lower part of the body
Brain expands and generates more that 250 000 neurons per minute. Formation of
complete chest and abdomen.
Eyes recognized behind closed eyelids, lung buds begin to develop, plates for hands
and feet begin to appear + olfactory lobe (smell) begins to develop.
6th Week: heart undergoes NB structural + functional changes. Tube-like shape
changes into heart with 4 chambers . (11-14mm long) day 36 arm buds visible.
8th Week: 30mm long where the face, mouth, eyes and ears are distinguished.
Stumpy fingers + toes appear
At this stage, sexual organs are developed, muscles and cartilage have developed
BUT clear neuromotor activity is absent.
INTERNAL ORGANS begin to fulfil their function with producing red blood cells &
stomach producing digestive juices.
3. The Fetal Stage
o The developing organism is known as a fetus
o Further differentiation now takes place so organs/systems can function
effectively
o During 3rd month – the penis + scrotum of male fetus and the labia of female
fetus appears.
o Male organs develop faster
o A connection between nervous system and muscles with spontaneous
movement
o Don’t feel movement until 4th month (now feels movements)
o During 4th month – face becomes more human, and body starts to lengthen.
o Heart beats between 120-160 times a minute
o Activities include thumb sucking , hiccupping, and all reflexes found in
newborns
