The Ovarian and Uterine Cycles an Online Exploration

Name ______Period ______Accelerated Biology The Reproductive and Endocrine Systems The Ovarian and Uterine Cycles – An Online Exploration

Go to the website below. A link to the website is provided on my wiki. As you watch the animation, answer the questions below. You do not need to use complete sentences. http://www.sumanasinc.com/webcontent/animations/content/ovarianuterine.html

Read the Introduction. 1. What is another name for an egg? Note: The narrator will use this term, rather than egg or ovum.

2. How many immature eggs is a female born with?

3. What three events take place in the ovarian cycle?

4. What two events take place in the uterine cycle?

5. The lining of the uterus sloughs off in a process called ______or ______.

Click on the “Narrated” button on the left side of the screen. Then click on the “Events of the Ovarian and Uterine Cycle” link that appears. Click “Play” and answer the questions below. You can pause and rewind if you need to.

6. How long does the ovarian cycle last?

7. What is ovulation? On what day does it occur?

8. What do the follicle cells that are left behind after ovulation form into?

9. What hormones does the corpus luteum secrete?

10. What happens to the corpus luteum at the end of the ovarian cycle if a woman is not pregnant?

11. What does the uterine cycle begin with? Click on the ”House” Icon located in the lower right corner of the window. Once again, click on the “Narrated” button on the left side of the screen. This time, click on the “Pituitary and Ovarian Hormones Control the Ovarian Cycle” link that appears. Click “Play” and answer the questions below. You can pause and rewind if you need to.

12. What two hormones are produced in the anterior pituitary gland?

13. What do FSH and LH stimulate?

14. What hormone does the growing follicle secrete?

15. Around day 12 of the ovarian cycle, an increase in estrogen causes what changes in the pituitary gland? Is this an example of positive or negative feedback?

16. On what day of the ovarian cycle does LH reach its peak? What does this LH surge trigger?

17. What two hormones are secreted by the corpus luteum?

18. What do estrogen and progesterone inhibit? What effect does this have?

Click on the ”House” Icon located in the lower right corner of the window. Once again, click on the “Narrated” button on the left side of the screen. This time, click on the “Ovarian Hormones Control the Uterine Cycle” link that appears. Click “Play” and answer the questions below. You can pause and rewind if you need to.

19. At the beginning of the uterine cycle, why does menses occur?

20. What effect does increasing levels of estrogen have on the uterus?

21. The corpus luteum secretes estrogen and progesterone. What effect do these hormones have on the uterine lining?

22. What happens to the corpus luteum at the end of the cycle if the egg is not fertilized or implanted?

23. What happens to the uterine lining as a result of the corpus luteum breaking down?