Prenatal
Development
October 7, 2011
Good Morning! 3/6/14
Today’s
Turn in Portfolio Entry #2
Finish Prenatal Development Video
Start Prenatal development notes
Interims – Clarity issue
Next
Agenda:
week:
Prenatal development
Vocabulary
Amniotic
Fluid – protects the developing
baby, cushions against bumps or falls
Conception – when the ovum and a
sperm unite
Embryo – 2nd stage of pregnancy: 3rd-8th
week. Rapid growth.
Fetus – 3rd stage: 9th week to birth
Vocabulary
Ovum
– a female cell or egg
Placenta – Tissue rich in blood vessels.
Provides path to nutrition.
Umbilical cord – brings nourishment to the
baby and takes waste away. Stiff and
firm like a garden hose, filled with water.
Uterus – organ in a woman’s body where
the baby develops.
Conception
Woman’s
body releases an ovum that
travels through the fallopian tubes to the
uterus.
Meets up with a sperm and is fertilized.
Pregnancy begins!
3 Stages of Pregnancy
Period
of the Zygote – Lasts for 2 weeks
Period of the Embryo – 3rd-8th week
Period of the Fetus – 9th week to Birth
Period of the Zygote
The
zygote (fertilized egg) travels down
fallopian tubes and attaches to uterus
Uterus provides soft, warm bed and a
source of nourishment
Zygote grows by cell division – from 1 to a
mass of cells
At end of this period, zygote is the size of
a pinhead
Period of the Embryo
2nd
Stage of pregnancy – 3rd-8th week
Embryo grows rapidly and goes through
lots of important changes
Mass of cells develop into major systems –
heart, lungs, bones and muscle
A sac filled with fluid forms around the
embryo for protection
Period of the Embryo
Sac
is filled with amniotic fluid – cushions
baby against bumps and falls
The Placenta develops – blood vessels
carry food and oxygen to the placenta
Umbilical cord brings food and oxygen to
baby and takes waste away
What would happen if the cord were
pinched?
Period of the Fetus
3rd
stage – 9th week until birth
As the baby grows, the fluid around baby
and the uterus expand also
Body is developing so it can live
independent of the mother
Fetus gains weight rapidly – from thin and
wrinkly to smooth and rounder
Fetus
Can
do many things before birth – suck its
thumb, cough, sneeze, yawn, kick, hiccup
and cry.
Can live outside of the uterus by the 7th
month, but only with lots of medical help
Premature baby – delayed development
Group Activity
Write
the following titles on each piece of
paper:
Period of the Zygote
Period of the Embryo
Period of the Fetus
Each
person writes one fact until each
has written on each paper and you have
run out of facts
Preparing for birth
During
the 9th month, baby shifts
downward – dropped into the birth canal
This shift is called “lightening” – could take
place several days or weeks before labor
begins
Fetus is typically upside down at this point
– easiest and safest position for birth
Fetus is less active – less room to move
Preparation
Mothers
skin and muscles are stretched
Uterus and abdomen can be stretched up
to 60 times their original size
Return to close to normal size within 6 weeks
or so after birth
After
born
37-42 weeks, the baby is ready to be
0
