An ecosystem is self-sustaining as long as organ- isms have sufficient quantities of energy, oxygen, minerals, and water. when organisms die, some of these materials are recycled back to plants in the ecosystem primarily through the activity

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.

yes we can.   a lady urinates from her urethra.