If a cell displays a great amount of activity, one possible reason for this could be that it has large quantities of

mitochondria

Explanation:

In cells where there is a high energy demand large numbers of mitochondria are found. The tail of a sperm contains many mitochondria and they run in a spiral like form along the length of the tail. In heart muscle cells about 40% of the cytoplasmic space is taken up by mitochondria.

affects the water bodies: excessive use of fertilizers causes eutrophication. the fertilizers which are used on plants affect the quality of land on which it is used, further causing erosion of soil. the fertilizers used on plants contain harmful chemical fumes which affect the environment.

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.