Introducing the Multilingual Illustrated DVD
Explore the fascinating imagery and facts presented in The Biology of Prenatal Development at your own pace. Each clip from the program is accompanied by its corresponding written script. Select Play Movie to watch any clip. Select See Snapshots to view high resolution images. See the program script and subtitles in 88 languages by using the Choose Language drop-down menu and clicking Refresh. Subtitles are displayed in your chosen language and may be turned on and off by clicking the button found in the lower right corner of the movie player. A "full screen" option is also available by clicking the button.
This program is distributed in
the U.S. and Canada by National Geographic and EHD.[learn more][hide]
By 16 weeks, procedures
involving the insertion
of a needle into the abdomen
of the fetus
trigger a hormonal
stress response
releasing noradrenaline,
or norepinephrine,
into the bloodstream.
By 20 weeks the cochlea,
which is the organ of hearing,
has reached adult size
within the fully developed
inner ear.
From now on,
the fetus will respond
to a growing range of sounds.
By 21 to 22 weeks
after fertilization,
the lungs gain some ability
to breathe air.
This is considered
the age of viability
because survival
outside the womb
becomes possible
for some fetuses.