Endocrine interactions, Biology

Endocrine Interactions

At the beginning of menstruation the inhibitory influence of the corpus luteum on the pituitary is removed and FSH is secreted in increasing amounts. This stimulates the growth of the young follicles, and they grow, they release increasing quantities of estrogens. The high estrogen content of the blood causes the pituitary to diminish its production of FSH and increase the output of LH. Ovulation occurs when the balance between FSH and LH has swung sufficiently in favour of LH.

223_Endocrine Interactions.png

Figure:  Diagram showing changes in the endometrium, the ovaries and the circulating ovarian hormones during the menstrual cycle.

There is evidence that small amounts of are produced by the preovulatory follicle, and this hormone may be involved in the ovulatory process perhaps through its action on the brain or the anterior hypophysis. After ovulation, the corpus luteum begins to form in the ruptured follicle under the influence of LH. Gonadotropins activate the corpus luteum and cause it to secrete progesterone and small amounts of estrogen. If a fertilised egg is not produced, functional degeneration of the corpus luteum begins eight to ten days after ovulation. The onset of menstrual bleeding correlates with the withdrawal of progesterone and, to a lesser extent of estrogen in the breakdown of the endometrial blood vessels with subsequent bleeding remain largely unknown. If the egg is fertilised, the pituitary continues to release luteinizing hormone, and the corpus luteum increases in size and augments its output of hormones. Secretory competence of the corpus luteum diminishes slowly after the fourth month of pregnancy, although it remains structurally intact until the end of pregnancy. The placenta, rather than the ovary, is the principal source of progesterone and estrogen during the latter half of pregnancy. Removal of the ovaries after mid pregnancy neither terminates pregnancy nor diminishes the levels of the two types of steroid hormones in the circulation.

 

 

 

Posted Date: 1/16/2013 11:50:40 PM | Location : United States







Related Discussions:- Endocrine interactions, Assignment Help, Ask Question on Endocrine interactions, Get Answer, Expert's Help, Endocrine interactions Discussions

Write discussion on Endocrine interactions
Your posts are moderated
Related Questions
Explain Procedure for the use of Light Microscope? Now carry out the exercise following the steps enumerated herewith. 1. Place the microscopic slide with any specimen on th

Explain the Disadvantage of Contact Plate Method? These plates are suitable for sampling the surfaces having low contamination, like pre-cleaned and sanitized surfaces. This is


15 character of protozoa

define respiration in diffrent types of animals

A glycogen molecule having entirely of glucose units, many of that are linked in long chains through α1-4 bonds.  Furthermore,  every  10  units  or  so,  the  chain  is branched

What is leaf cuticle? Leaf cuticle is a thin waxy layer made of waxes and cutin on the outer surface of the leaf epidermis. Its function is near control the cellular transpirat

List the benefits of exercises. Benefits of exercise are : - improves sugar control - decreases HbA1c level - decreases  blood pressure - decreases triglyceride lev

Explain the Air Sampling? Microorganisms may be present in air of processing facility and have an impact on the quality and safety of foods processed and handled there. To avoi

Q. How different is the growth according to the biotic potential of a viral population from the growth according to the biotic potential of a bacterial population? The growth c