1a) X = FSH (follicle stimulating hormone) Z= LH (luteinizing hormone)
1b) W=Estrogen, Z= progesterone
1c) W + Z (Estrogen and progesterone) display negative feedback loops
2d) See separate sheet
2e) 14th day of cycle = ovulation day
2f) Temperature remains somewhat constant, but it reaches 38.4 degrees Celsius at ovulation and then gradually decreases during the rest of the menstrual cycle until menses (some exceptions apply).
2g) If no corpus luteum exists then estrogen and progesterone will not be released and therefore there is no ovulation, hence no change in the body temperature, but when the corpus luteum is present there is a clear rise in temperature during ovulation.
3h) X = ovulation occurs Z = menses starts
3i) Estrogen is released sometime in between days 6 and 13 in the follicular phase (W on graph).
3j) Estrogen and progesterone are released in between days 15 and 28 during the luteal phase (Y on graph)
4k) LH causes a decrease in progesterone levels, but an increase in estrogen levels.
4li) X = point where estrogen level is high and progesterone is low (day 14)
4lii) Z = point where estrogen and progesterone levels are high (day 23, cycle 2)
4m) Many oocytes being to develop and all of one die off. The one remaining moves on to produce an egg while the other polar bodies (follicle cells) will transform into the corpus luteum. One corpus luteum is required to release estrogen and progesterone in order to make sure a properly thickened endometrium exists (3 eggs will attach in different places in the case of identical triplets which occurs due to splitting of zygote into 3 separate totipotent cells which would all carry the same DNA). Therefore there would only be one corpus luteum in the ovaries of a woman who has given birth to identical triplets.
4n) Osteoporosis can be prevented by eating balanced meals including supplements of calcium, vitamin D etc. in proper quantities. In terms of lifestyle, being