Plants produce oxygen as a by-product of photosynthesis, but most plants cannot live in anoxic soils. Anoxic soils form when soils gets compacted and you lose the space between the soil particles. Why can't most plants live in such anoxic conditions? (hint: look at the structure of the cell from the pre-lab)

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 : )