What is the cause of the “red tide”?
a large oil or gasoline spill gives the water its reddish color
the blood from fish or other marine animal in a massive “die-off”
a sudden growth spurt or “bloom” in algae
a toxic condition of the water cause by beach pollution

the corpus luteum secretes estrogens and progesterone. the latter hormone causes changes in the uterus that make it more suitable for implantation of the fertilized ovum and the nourishment of the embryo. if the egg is not fertilized, the corpus luteum becomes inactive after 10–14 days, and menstruation occurs.

i hope this : )