1. identify the human body systems and their functions.

Cardiovascular system - contains all of our muscles necessary , skeletal system- contains the bones to create the shape of the body and respiratory system which allows us to breathe

the level of progesterone is low at the pre-ovulatory phase of the cycle but it gradually increases and the levels are high at the luteal phase. if pregnancy occurs, the level of progesterone will be high throughout the pregnancy.

if egg is fertilized and the mother gets pregnant, progesterone starts preparing the uterus for the implantation. it starts building up the lining of uterus and make it hostile of the period of pregnancy.