Egg Production

1. Egg Production

2. Females are born with all the eggs they will ever have for their entire life.

3. At about age 10, the average girl starts puberty. This is when menstruation (period occurs).

4. The Average Menstrual Cycle • Days 1-4 Menstrual flow leaves the body Body produces a hormone (FSH) that selects the “egg of the month”

5. The Average Menstrual Cycle • Days 5-12 • Estrogen causes the lining of the uterus to thicken • Ova (egg of the month) starts to mature

6. The Average Menstrual Cycle • Days 13-14 Ovulation occurs---this means the egg is released from the ovary This means fertilization can occur for about 1 week from now

7. The Average Menstrual Cycle • Days 15-20 Fertilization can occur Your body starts to produce progesterone to prevent additional egg release Remember this is still a fertile time

8. The Average Menstrual Cycle • Days 21-28 • The wall of the uterus is thickened • If egg is not fertilized, it will begin to loosen and eventually shed itself and get ready for next month

9. The Average Menstrual Cycle • Remember this is the “normal” cycle • Not every female follows this cycle • Not every female has a 28 day cycle • Not female ovulates in the middle of their cycle • This is the average or normal cycle but you cannot be sure how your body works

10. Sperm Production • Testes are where sperm are produced • Unlike females, men continue to produce sperm for the rest of their life. The average male produce 12 billion sperm per month

11. Sperm • Before intercourse, the penis fills with blood causing the sperm to become erect (hard) • Ejaculation occurs (semen filled with sperm are released) • Sperm can live up to 72 hours---most live between 34 to 48 hours

12. Sperm • Think about this: • The average ejaculate contains about 300 million sperm • 200 of those sperm will live long enough to enter the female body • It only takes one of them to fertilize an egg

13. How is the sex determined? This is an egg. It is always female. It has 22 chromosomes plus the X (female) chromosome for a total of 23 chromosomes.

14. How is the sex determined? This is a sperm. There are male and female sperm. Each sperm has 22 chromosomes plus and X (female) or Y (male) for a total of 23 chromosomes

15. So how do multiple births occur? • Fraternal twins are not • identical. For some • reason more than one • egg is released and • fertilized by different • sperm. Each fertilized • egg has it’s own sac.

16. Now….how many chromosomes does a fertilized ovum have? • Did you say 44? Wrong! Try again! • Did you say 46? You are brilliant! • There are 22 from the egg • There are 22 from the sperm • There is 1 female from the egg • Either 1 male or female from the sperm SO THAT MAKES A TOTAL OF 46

17. Fraternal Twins • Each baby has it’s own amniotic sac so they grow separately • Each baby has it’s own placenta (gives baby nourishment) • Babies may be the same or opposite sex • Babies may look similar because they have the same parents • These babies may be the same or different sexes.

18. Paternal Twins • These are also known as identical twins. • For some reason a fertilized egg splits. • These babies share a sac • and placenta

19. More than 2 babies… • The same concepts apply to any multiple birth. For example, you can have triplets and 2 are identical and 1 fraternal • You could have triplets that are all identical. • It all depends on how fertilization occurs

20. Paternal Twins • These babies will share an amniotic sac and placenta • They will always be the same sex because it is one egg that split. • They will always look exactly the same because it is one egg that split so all genes/chromosomes are the same.

21. How does the fertilized occur develop? • Once an egg is fertilized it goes through 3 stages. • Zygote • Embryo • Fetus

22. Zygote • This is the stage between conception (egg and sperm uniting) and 2 weeks. • Fertilized egg attaches to the wall of the uterus. • Wall of the uterus thickens (blood and tissue) • At end of this time it is the size of a pin head • You may not even suspect you are pregnant at this time

23. Embryo • This is between 3-8 weeks. • Many things develop: • Body systems (respiratory, circulatory….) • Amniotic fluid (surrounds & protects) • Placenta (attaches to wall of uterus to filter food and oxygen to the baby) • Umbilical cord (connects placenta to belly button of baby)

24. Fetus • 9 weeks until birth occurs (40 weeks) • Movement begins • Starts immediately however mom doesn’t feel until 4-5 months • Amniotic fluid increases • Uterus continues to grow • Organs begin to fully develop • Fetus grows rapidly

25. Genes, Chromosomes, TraitsWhat’s it all about? Physical traits are observable characteristics determined by specific segments of DNA called genes. Multiple genes are grouped together to form chromosomes, which reside in the nucleus of the cell.

26. Every cell (except eggs and sperm) in an individual’s body contains two copies of each gene. This is due to the fact that both mother and father contribute a copy at the time of conception. This original genetic material is copied each time a cell divides so that all cells contain the same DNA. Genes store the information needed for the cell to assemble proteins, which eventually yield specific physical traits.

27. Most genes have two or more variations, called alleles. For example, the gene for hairline shape has two alleles – widow’s peak or straight. An individual may inherit two identical or two different alleles from their parents. When two different alleles are present they interact in specific ways. For the traits included in this activity, the alleles interact in what is called a dominant or a recessive manner.

28. What that means… • The traits due to dominant alleles are always observed, even when a recessive allele is present. • Traits due to recessive alleles are only observed when two recessive alleles are present.

29. How traits are handed down Although science knows a lot about traits and chromosomes, there is still some disagreements about whether some of the following traits are dominant or recessive. There may never be 100% agreement but the following is the most widely agreed upon.

30. For Example A widows peak is a dominate trait. 2 dominant traits = = 1 dominant +1 recessive 2 recessive traits =

31. Ear Lobes • Attached ear lobes are recessive Detached ear lobes are dominant

32. Tongue • Rolled tongue is a • dominant trait. This is a recessive trait.

33. Look at the handout about dominant and recessive traits.

34. Cleft Chin • This is a • dominate • trait.

35. Dimples Dimples are a dominant trait.

36. Roman Nose This is an example of a roman nose.

37. Handedness Right handedness is a dominant trait while left handedness is recessive.

38. Freckles • These are dominant

39. Hair • Curly hair is dominant • Straight hair is recessive

40. Hand Clasping • Clasp your hands • together. • If your right thumb • is on top, that is • dominant---left is • recessive.

41. Today’s Summarizer Think about your family. Choose three traits that you see in your family that you have. Using the paper, tell whether they are dominant or recessive.

45. Today’s Bell Ringer11/6/12 • Define the following words and write a sentence using the word. • Infertility • Invitro Fertilization

46. Partner Activity Draw a Venn Diagram Invitro Fertilization Artificial Insemination

47. Prenatal Testing • What does prenatal mean? • It refers to the time before birth • These test can be done to determine specific birth defects • No test is 100% safe or accurate

48. Ultrasound http://youtu.be/cK0_eC7PIgY

49. 3D Ultrasound

50. Ultra Sound • This test is used for the following: verify due date sex of baby’ development is on schedule skeletal or organ defects Risks are unknown but considered relatively safe for both mom and baby