Name _____________
Block ____
Life’s Greatest Miracle Virtual NOVA Activity
Background Knowledge- Take time to first review the structures and functions of the
male and female human reproductive systems.
Directions- Watch the film Life’s Greatest Miracle by PBS Nova and take notes on which
systems and body parts develop in each phase of the developmental process using the
note guide below.
PBS. “Life’s Greatest Miracle.” Nova. PBS Online. WGBH Educational Foundation. 2020.
November 20, 2001. Retrieved July 28, 2020,
https://www.pbs.org/wgbh/nova/video/lifes-greatest-miracle/.
Developmental Chart
1. Human pregnancy lasts approximately ____ weeks.
2. It can last anytime between _____ and ____ weeks after _____________ and still be considered a normal timeframe.
First Trimester
3. An _______ becomes fertilized when a __________ penetrates it, creating a _____________.
4. For the first eight weeks, the developing baby is called an ______________. It looks like a ________________.
5. At about _____ weeks, the neural tube, which becomes the ___________ and spinal _________, is forming.
6. At about ______ weeks, the ___________ begins to pump _________. Tiny ___________ buds appear, __________
and ___________ are formed, ______________ and ________ develop.
7. During the first trimester, which lasts up to _____ weeks, all major body ____________ and systems are formed but
not completely ________________.
8. This is a critical period for development of the ____________, central ______________ system, upper and lower
____________, __________ and ___________, ____________ and palate, and most organs. Any damage at this
stage can result in major damage or __________________.
9. At _____ weeks, when most _________________ have formed, the embryo is called a ______________.
Second Trimester
10. The fetus moves, ___________, _________________, and can hear the mother’s _______________.
11. It begins to ______________ and ________________ at regular intervals.
12. The skin changes from a transparent _____________ to a wrinkled _________, and is covered with soft, fine ______.
13. By the end of the _____the month, the central nervous system is past its most vulnerable stage. As its development
continues, though, it remains susceptible to functional ______________ throughout pregnancy.
14. The __________, ______________, and external ________________ continue to be susceptible to functional defects
and lesser deformities throughout the second trimester, which lasts until about Week ______.
Third Trimester
15. Body growth slows down, while _________ growth continues and the _______ grows larger during the third trimester.
16. The fetus begins developing its own _________________ system.
17. Rapid ____________ growth continues. The fetus can open and close its _________, suck its ___________, kick,
_______________, and __________.
18. It responds to ______________ and _______________, if born as early as the ____________ month, would have a
good chance of surviving.
Reflection Activity
Draw a 40-week timeline on a separate sheet of paper with a partner in class. Fill in the
timeline using your notes about each stage of embryonic/fetal development.
Life’s Greatest Miracle Virtual NOVA Activity
ANSWER KEY
1. Human pregnancy lasts approximately 40 weeks.
2. It can last anytime between 36 and 42 weeks after fertilization and still be considered a normal timeframe.
First Trimester
3. An egg becomes fertilized when a sperm penetrates it, creating a zygote.
4. For the first eight weeks, the developing baby is called an embryo. It looks like a tadpole.
5. At about three weeks, the neural tube, which becomes the brain and spinal cord, is forming.
6. At about four weeks, the heart begins to pump blood. Tiny limb buds appear, ankles and wrists are formed, and
fingers and toes develop.
7. During the first trimester, which lasts up to 10 weeks, all major body organs and systems are formed but not
completely developed.
8. This is a critical period for development of the heart, central nervous system, upper and lower limbs, eyes and
ears, teeth and palate, and most organs. Any damage at this stage can
9. result in major damage or deformity.
10. At eight weeks, when most organs have formed, the embryo is called a fetus.
Second Trimester
11. The fetus moves, kicks, swallows, and can hear the mother’s voice.
12. It begins to wake and sleep at regular intervals.
13. The skin changes from a transparent pink to a wrinkled red, and is covered with soft, fine hair.
14. By the end of the fourth month, the central nervous system is past its most vulnerable stage. As its development
continues, though, it remains susceptible to functional defects throughout pregnancy.
15. The eyes, teeth, and external genitalia continue to be susceptible to functional defects and lesser deformities
throughout the second trimester, which lasts until about Week 30.
Third Trimester
16. Body growth slows down, while brain growth continues and the head grows larger during the third trimester.
17. The fetus begins developing its own immune system.
18. Rapid brain growth continues. The fetus can open and close its eyes, suck its thumb, kick, stretch, and cry.
19. It responds to light and sound and, if born as early as the seventh month, would have a good chance of surviving.