By means of the sodium-potassium pump, living human cells pump three sodium ions out of the cell in exchange for two potassium ions pumped in; comparing ion concentrations across the cell membrane, inside to outside, potassium measures about 40:1, and sodium, about 1:10.
However, in some cases, the enlarged ovary may twist or become dysfunctional. Ovarian cancer and benign tumors may also lead to an enlarged ovary. Common causes of an enlarged ovary include: Corpus luteum cyst (cyst present in the second half of the menstrual cycle) Dermoid cyst (benign tumor also known as a teratoma) Follicle cyst (cyst that forms during the menstrual cycle) Endometrioma (endometriosis affecting the ovary)
Causes of Premature Ovarian Failure There are several known causes for premature ovarian failure: genetic conditions that affect the X chromosome (Turner Syndrome and Fragile X syndrome), autoimmunity (immunity against oneself), surgical loss of ovarian tissue, or loss of ovarian tissue due to chemotherapy and/or radiation.