SCIENCE in GRADE 10 a lesson for good academics

menstrual cycle, grade 10 lesson 3rd quarter

1. THE MENSTRUAL CYCLE By : pau, jewel, and angel.

2. The menstrual cycle is a natural process that happens in the female body to prepare for pregnancy. It happens every month (about every 28 days) and is controlled by special chemicals called hormones. The cycle starts when a girl is around 10 to 13 years old and continues until she is around 40-50 years old. THE MENSTRUAL CYCLE

3. FOUR MAIN STAGES OF MENSTRUAL CYCLE

4. 4 STAGES

5. MENTRUATION PHASE (1-5) This is when a woman has her (menstruation) period. The body sheds the thick lining of the uterus (called endometrium) breaks down and comes out as blood. This happens because there is no pregnancy.

6. 2. FOLLICULAR PHASE (5-14) The pituitary gland in the brain releases a hormone called FSH (Follicle Stimulating Hormone). FSH makes one of the eggs in the ovaries grow and mature inside a follicle. the ovaries release estrogen, which helps the uterus lining grow thick again, getting it ready to support a possible pregnancy.

7. 3. OVOLUTION (14) A surge of another hormone called LH (Luteinizing Hormone) causes the ovary to release the mature egg. The egg travels into the fallopian tube, where it waits for sperm to fertilize it. This is the only time in the cycle when a woman can get pregnant. Ovulation is crucial for reproduction.

8. 4. LUTHEAL PHASE (14-28) After ovulation, the empty follicle in the ovary becomes a structure called the corpus luteum. The corpus luteum makes a hormone called progesterone, which keeps the uterus lining thick and ready for a fertilized egg. Progesterone keeps the uterus ready for pregnancy. If no pregnancy occurs, the body resets for the next cycle.

9. 1 . Menstrual Phase: The body clears out the old lining (period). 2. Follicular Phase: The egg matures, and the uterus lining starts to grow. 3. Ovulation: The egg is released and ready for fertilization. 4. Luteal Phase: The uterus lining stays thick in case of pregnancy or breaks down if no pregnancy occurs. CONCLUSION

10. THANK YOU ~~~