1. Aim: How can hormones influence the reproductive cycles in humans?

2. Who am I? Our bodies change. You grow taller & bigger. Our sexual organs mature. Hair appears where there was no hair before. You may begin to feel attracted to another individual. An Adolescent Going Through Puberty

3. Control of Reproductive Systems The Hypothalamus & Pituitary Gland produce hormones that influence the gonads to produce sex hormones

4. Hormonal Control of the Female Reproductive System: Beginning at puberty, female reproductive organs undergo a cycle of changes that prepare the body for the possibility of pregnancy. The hypothalamus, the pituitary gland, and the ovaries produce hormones that control this cycle of change. What is this cycle of change called? Menstrual Cycle

5. Menstrual Cycle (28 Days) Follicular Phase (14 Days) Ovulation (1 Day) Corpus Luteum Phase (14 Days)

6. Menstrual Cycle Stages 1)Follicular Stage: FSH (follicle stimulating hormone) secreted from pituitary stimulates the ovary to produce estrogen Follicle- cells that surround & protect egg. FSH also causes egg to mature inside a follicle Estrogen causes the lining of uterus to begin to thicken 10-14 days

7. How does a woman get ready to get pregnant? An egg is produced & the lining of the uterus thickens to receive the embryo

8. 2) Ovulation LH secreted by the pituitary increases and the follicle bursts Release of an egg into the oviduct (This is when a woman can get pregnant) Around day 14

9. 3) Corpus Luteum Phase Broken follicle is now a corpus luteum Secretes estrogen & progesterone to further thicken the lining of the uterus 10-14 days

10. MENSTRUATION Occurs if there is NO fertilization Hormones decrease Uterine lining sheds 3-7 days

11. Uterine Lining A woman gets rid of the old uterine lining & the unfertilized egg (if the egg is NOT fertilized)

12. Hormones & the menstrual cycle Which hormones peak before ovulation? Which hormone peaks after ovulation? http://www.msnbc.com/ne ws/wld/graphics/menstrual _cycle_dw.htm

13. Girls Secondary Sex Characteristics Hips widen Pubic Hair Breasts enlarge Due to the hormones estrogen and progesterone.

14. Hormonal Regulation of the Testes: Beginning at puberty, the pituitary gland secretes FSH & LH. The rising levels of these hormones stimulate the testes to produce testosterone. Testosterone stimulates the production of sperm.

15. Boys Secondary Sex Characteristics Voice Deepens Facial Hair Muscular Development Pubic Hair Due to the hormone Testosterone.

16. What mechanism is involved in the control of reproduction? FEEDBACK MECHANISM