Human Development Video

1. Name the molecule that carries our genes. DNA
2. Genes are located in the __DNA___________________________.
3. What is the number of sperm the average man produces in a second? 1000
4. How can one person produce so many different combinations of genes? miosis
5. Most human cells have a total number of __46________ chromosomes.
6. The gene shuffling that occurs from mitosis results in a great amount of this? diversity
7. Where in the female reproductive tract does the egg wait for fertilization? fallopian tube
8. How does the egg move through the Fallopian tube? cilia and muscular contraction
9. Approximately how many sperm are contained within one teaspoon of seminal liquid? 300 million
10. What are some of the challenges that sperm face once entering into the vagina? they must escape or die, acididty
11. Describe the milestone event that takes place two weeks after conception? gasterolation
12. Describe the size and physical characteristics of the fetus at 4 and 1/2 weeks following conception. 1/5 of an inch long, the backbone curves like a tail and the brain is developing on the side of the face is a eye
13. If the DNA in a single cell were stretched out, how long would it be? 6 ft long
14. After about how many weeks can doctors determine the sex of the baby from ultrasound? 18 weeks
15. Aside from the ultrasound, how can a doctor determine the sex of a baby? chromosomes
16. At what point does the embryo become a fetus? 2 months after fertilization
17. When does the placenta begin to form? in the early weeks
18. What is the fetus’s job in the last trimester? to grow
19. Why are human births so much more dangerous than other mammals? the human brain is 3 to 4 times bigger, narrower pelvis