Human Growth and Development (DEP 2000) Prof. Rabulan, Doral College Unit 1: Prenatal Development and Newborn Infants Name: Jenna Cordero Date: ___________________ Life’s Greatest Miracle (PBS Nova) Video Comprehension Questions 1. How many human babies are born each day? • 365,000 2. How many cells are there in the human body? • 100 trillion cells 3. What does the video say is the "fundamental urge" for all life? • To reproduce 4. What is DNA "very good" at? • Making copies of itself 5. How does the DNA of a bacterium compare to its parent's? • Exact replicas 6. What risk is there for a species that only reproduces by cloning? • All members of the population would have the same immune system, so if the person cloning has a weak immune system, one parasite could wipe us all out 7. How does the DNA of sexually produced offspring compare to the DNA of the parents? • Combination of mother and father 8. How many sperm does the average human male produce each second? • 1000 9. What process creates sperm cells and egg cells? • meiosis 10. How many chromosomes are there in a normal human body cell? • 46 Human Growth and Development (DEP 2000) Prof. Rabulan, Doral College Unit 1: Prenatal Development and Newborn Infants 11. What happens to the genes when two chromosomes "embrace"? • They exchange DNA 12. What is the advantage of diversity within a species? • Higher chances of survival of a new generation 13. When does a human female produce her eggs? • When she is a fetus in her mother’s womb 14. How many eggs does the average human female release per month? • 1 15. What is an egg missing that it needs to survive? • DNA from sperm 16. About how many sperm are released into the vagina? • 300 million 17. What danger confronts sperm in the vagina? • Acidity of the vagina 18. What does the sperm need in order to move through the egg’s zona? • Proteins from the sperm must hook up with the egg’s surface. 19. How much time passes between fertilization and the first division of the zygote? • 24 hours 20. What happens if the dividing zygote accidentally separates into two? • Creates two embryos, twins 21. After fertilization, how long does it take the blastocyst to arrive in the uterus? • 5 days Human Growth and Development (DEP 2000) Prof. Rabulan, Doral College Unit 1: Prenatal Development and Newborn Infants 22. What risk does the blastocyst face after it attaches to the uterus? • Could be attacked by the mother’s immune system 23. What is gastrulation? • Cells organize into an embryo deep within the uterine lining 24. What will the lower layer of cells develop into? • Lungs, liver, and the lining of digestive track 25. What will the middle layer of cells develop into? • Heart, muscles, brain, and blood 26. What will the outer layer of cells develop into? • Spinal cord, brain, skin, and hair 27. How long is the embryo after 4 ½ weeks? • 1/5 of an inch 28. True or false: All cells have the same genes. • true 29. What does a gene do when it has been “turned on?” • Produce proteins 30. What do the following proteins do? a. collagen: fiber that makes up much of your skin, tendons and bones b. crystallin: helps make the lens of your eye clear c. actin and myosin: move muscle fiber d. hemoglobin: carries oxygen from lungs to the rest of the body 31. How do cells communicate with each other? Human Growth and Development (DEP 2000) Prof. Rabulan, Doral College • Unit 1: Prenatal Development and Newborn Infants Chemical messages 32. How is the Y chromosome different from the X chromosome? • The Y chromosome is one-third the size of the X chromosome and contains about 55 genes while the X chromosome has about 900 genes 33. From where does the baby get its nutrients? • The mother’s blood 34. Do the baby's and mother's blood ever mix? • No 35. How old is the fetus when it gains the ability to hear sound? • 5 months 36. What is the main job of the fetus during the last trimester? • To grow 37. What does myelin do? • Wraps around the long connections of brain cells, helps nerves move faster, enhances brain power. 38. Why is birth more dangerous for humans than for other animals? • The human brain is bigger than the human pelvis so sometimes there’s not enough room for