1. MENSTRUAL CYCLE: BEGINS AT PUBERTY AND CONTINUES TO ABOUT LATE- 40’S. Has 4 Phases: FOLLICULAR, OVULATION, LUTEAL, MENSTRUATION

2. FOLLICULAR PHASE: -Low estrogen levels cause the PITUITARY GLAND to secrete FSH (Follicle Stimulating Hormone) AND LSH (Leutenizing Stimulating Hormone) ** Egg DEVELOPS & MATURES in this stage (~ 10 DAYS)

3. OVULATION: * Shortest phase * Occurs midway through cycle - Lasts 3-4 days * Follicle ruptures & a mature egg is released into one of the FALLOPIAN TUBES.

4. LUTEAL PHASE: * Begins after egg is released & lasts about 10-14 days. * Formation of the CORPUS LUTEUM (increases levels of ESTROGEN & PROGESTERONE) * Uterine lining thickens * Fertilization of egg GREATEST

5. MENSTRUATION PHASE: * If not fertilized, egg passes through uterus w/in 2-3 days from ovulation * Corpus Luteum disintegrates * Estrogen levels drop, uterine linig detaches and along w/blood and the unfertilized egg is discharged through the vagina.

6. * Average period of menstruation lasts 3-7 DAYS * New cycle begins w/first day of menstruation * Continues in females until ~AGE 50 when follicles mature, rupture or disintegrate causing MENOPAUSE

7. 4 PHASES OF MENSTRUAL CYCLE

8. Fertilization: Sperm egg

9. * Process of a single sperm joining an egg usually while in the FALLOPIAN TUBE. *Fertilized egg is called a ZYGOTE and has 46 CHROMOSOMES. WHAT IS FERTILIZATION?

10. TWINS FRATERNAL 2 separate eggs fertilized by 2 separate sperm. Boys, girls or one of each.

11. TWINS IDENTICAL 1 egg fertilized by 1 sperm Splits after fertilization. Same sex.

12. FETAL DEVELOPMENT * zygote undergoes mitosis * after 4 weeks zygote is called an EMBRYO

13. * AMNIOTIC SAC cushions and protects the developing embryo. * PLACENTA- the connection between mother & embryo in which it receives its supply of nutrients & oxygen.

14. * END OF 8 WEEKS EMBRYO CALLED FETUS, umbilical cord begins to form. * 9th month baby is called “Full Term”.

15. Full term baby is typically delivered vaginally. Sometimes baby is delivered by Caesarian (C- section).

16. DISORDERS Ectopic pregnancy- fertilized egg implants itself in fallopian tube, outside the uterus.

17. Cervical cancer - can be detected through a PAP SMEAR TEST. Aids: caused by HIV, transmitted through body fluids (semen, vaginal fluid, blood)- no cure.