You have isolated a microorganism from seawater that contains thylakoid membranes, gas vacuoles, and carboxysomes. it is most likely

a. e. coli.
b. caulobacter.
c. algae.
d. a cyanobacterium.
e. an ameba.

D. A cyanobacterium

Explanation:

Cyanobacteria have gas vacuoles, thykaloid membranes and carboxysomes

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 : )