Nova Online - Life's Greatest Miracle Print Friendly and PDF


In this activity, you will watch a video, Miracle of Life. In this program, the process by which egg and sperm join to create and embryo is shown. The video then continues to follow the fertilized egg as tissues and then organs develop, finally ending with the birth of the baby.

Note: This program may not be suitable for all viewers.
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1. DNA is very good at _________________________________________________

2. Why is sexual reproduction more advantageous than cloning? ___________________________

3. How many new sperm are created every day? _____________________________________

4. During meiosis, what happens to the matching X-shaped chromosomes? __________________________________________________

5. How is the egg pushed along within the Fallopian tube? _________________________________________________________________

6. To fertilize the egg, sperm encounter several obstacles, what is the last one they encounter before they penetrate the egg? ______________

7. The blatocyst must do two things to survive, it must break out of the zona and what else ? ___________________ _____

8. Two weeks after conception, the cells organize themselve into an ________________________, a process called gastrulation.

9. The three layers of cells created during gastrulation are destined for three different functions. Describe what each will become:

Bottom Layer __________________ Middle Layer _____________________ Top Layer __________________________________

10. Genes turn on and off to make proteins. Collagen is a protein that makes tendons and bones, keratin makes hair. Hemoglobin in the blood has what job? _____________________________________

11.An embryo with two X chromosomes will become a ________________. An embryo with the XY combination will become a ___________.

12. Two months after fertilization, the embryo is called a _____________________

13. What structure is used to gather blood and nutrients from the mother's blood and pass it to the umbilical cord? ______________________

14. At the end of pregnancy, the baby is growing myelin around its neurons. This growth increases its need for what nutrient? __________

15. Why is it harder for human babies to be delivered than other animals? ________________________________________