Investigation 8.5.1

1. Investigation 8.5.1 W = estrogen X = FSH Y = Estrogen & Progesterone Z = LH

2. b) Estrogen & progesterone are the ovarian hormones. c) W & Y, estrogen and progesterone exert negative feedback. e) Day 14 f) The temperature drops before ovulation and goes up after g) The corpus luteum controls post ovulation, so it causes the temperature to raise after ovulation. Without it, the temperature would remain the same.

3. h) X – Ovulation Z – Menstruation i) W is when the cells produce estrogen j) Y is when the corpus luteum produces estrogen and progesterone

4. k) LH increases levels of both, but it is difficult to see this from the graph.

5. l) i) Ovulation occurs at X, when estrogen levels are high. ii) Since the corpus leutum produces both estrogen and progesterone I would expect it too function on day Z. m) The triplets came from the same cleaved egg. n) Their cycles have stopped. o) We eat hormone fuelled meat.