How does menstrual cycle begin, Biology

Assignment Help:

Does the hypophysis-ovaries endocrine axis work in the same way during pregnancy as in non-pregnant women? If pregnancy does not occur how does another menstrual cycle begin?

The functioning of the hypophysis is changed during pregnancy. As estrogen and progesterone levels remain elevated during the gestational period the production of GnRH (gonadotropin-releasing hormone) from the hypothalamus is inhibited. The lack of GnRH therefore inhibits the secretion of FSH and LH from the hypophysis and a new menstrual cycle does not start.

If pregnancy does not happen the lowering of estrogen and progesterone levels stimulates the production of GnRH by the hypothalamus. This hormone then hastens the adenohypophyseal secretion of FHS and LH that in their turn stimulate the maturation of follicles and the starting of a new menstrual cycle.

 


Related Discussions:- How does menstrual cycle begin

Define in brief about the biomolecules, Define in brief about the biomolecu...

Define in brief about the biomolecules Some of the biomolecules, also known as compounds of life, form part of the structure of cell, and some of these are sources of energy fo

Functions of pantothenic and biotin acid for the body, Q. What are the func...

Q. What are the functions of pantothenic and biotin acid for the body? How are these vitamins obtained? Biotin also known as vitamin B8 is a vitamin that acts in the metabolism

Biochemical production , Biochemical Production: Plants are the foundat...

Biochemical Production: Plants are the foundation of a large variety of biochemical which are metabolites of both secondary and primary metabolism. But secondary metabolites ar

Cells, what are golgi apparatus

what are golgi apparatus

Enteric infectious viral disease, Match each item in Column A with the corr...

Match each item in Column A with the corresponding item in Column B regarding infectious diseases Column A Column B a. Pulmonary tuberculosis i. Enteric infectious protozoan diseas

Determine the part of the human visual system, Which is the part of the hum...

Which is the part of the human visual system where the receptors that sense light, i.e., the photoreceptor cells, are located? How do those cells work? The photoreceptor cells

Circulatory assist devices-open-heart surgery, Circulatory Assist Devic...

Circulatory Assist Devices :  Intra aortic balloon pump (IAUP) was introduced by Kantrowitz (19hX). It is also known as Counter pulsation or Diastolic augmentation.

Synthesis of hormones - testies, Synthesis of Hormones - Testies Leyd...

Synthesis of Hormones - Testies Leydig cells and the Sertoli cells are the steroid hormone synthesising cellular sites of the testis. Leydig cells are the major source of the

How has the position of the stomata changed in some plants, How has the pos...

How has the position of the stomata changed in some plants to prevent excessive water loss by transpiration? In some plants that have leaves that be given too much sunlight the

Ventilation of tracheal system - diffusion, Ventilation of Tracheal System ...

Ventilation of Tracheal System - Diffusion Gaseous exchange due to diffusion generally takes care of the oxygen needs of most small insects. Similarly fairly large but inactiv

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd