Presentation on theme: "The Menstrual and Ovarian Cycles. Vocabulary- The Hormones Secreted by Pituitary: – –FSH (Follicle Stimulating Hormone) Stimulates follicle to cause egg."— Presentation transcript:
The Menstrual and Ovarian Cycles
Vocabulary- The Hormones Secreted by Pituitary: – –FSH (Follicle Stimulating Hormone) Stimulates follicle to cause egg to mature – –LH (Luteinizing Hormone) Causes release of mature ovum (ovulation) Prepares uterus for implantation of fertilized egg
Vocabulary- The Hormones Secreted by Ovaries: ––E––Estrogen Causes uterine lining to thicken ––P––Progesterone: Works with estrogen to finish uterine lining thickening
Vocabulary- The Cycles Ovarian Cycle: – –Occurs for 28 days in the ovaries – –Process during which an ovum matures in a follicle and is released during ovulation – –After ovulation, a corpus luteum (yellow body) is left behind
The Ovarian Cycle: YouTube video clip The Ovarian Cycle: YouTube video clip
Vocabulary- The Cycles Menstrual (Uterine) Cycle: ––O––Occurs for 28 days ––P––Process during which uterine lining is preparing for fertilized ovum ––I––If fertilization occurs, this cycle stops until after birth ––I––If not fertilized, lining sheds (menstruation!) and cycle begins again
The Menstrual Cycle: The Video Clip
THESE TWO CYCLES ARE GOING AT THE SAME TIME!!!!!!!!!!!!!!!!!!! I REPEAT: THESE CYCLES RUN TOGETHER AT THE SAME TIME!
What is going on all at once?
The Beginning and the End: Menstruation Occurs if egg is not fertilized Days 1- 5 Corpus luteum (yellow body) breaks down – –This causes drop in estrogen and progesterone Uterine lining sheds FSH increases during
Phase 2: Follicular Phase Days 5 –13 Low estrogen = FSH to be released This stimulates growth of follicle – –Egg begins to mature Follicle matures causing estrogen levels up – –Uterine lining begins to thicken again
Phase 3: Ovulation Days Sudden rush of FSH Major SPIKE of LH – –This causes follicle to break and release egg into fallopian tube FERTILIZATION MOST LIKELY TO OCCUR AT END OF OVULATION!
Phase 4: Luteal Phase Days LH and FSH levels crash Corpus luteum forms from broken follicle Corpus luteum secretes estrogen and progesterone ––T––This thickens uterine lining to prepare for egg