Organisms must maintain which is a balance of internal conditions.

homeostasis

To achieve homeostasis, individual cells are able to keep the amounts of molecules inside and out at certain levels. Many cellular activities require that this balance be maintained with the surrounding environment.

this protocol describes a detailed procedure for intracellular flow cytometry staining.

"menstrual cycle is a complex cycle that consists of several processes. order of occurrence of steps in menstrual cycle are as follows:

1. high progesterone levels maintain the endometrium lining of the uterus.

2. endometrium lining breaks down and low levels of estrogen stimulate the pituitary to release fsh and lh.

3. fsh and lh stimulates the follicles to develop and the oocyte to produce estrogen.

4. rising estrogen levels suppress fsh production and development of other follicles.

5. a spike in lh causes follicle to rupture.

6. a breakdown of corpus luteum causes progesterone level to drop."