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

Tissue culture, Tissue culture The ability of a plant cell to give r...

Tissue culture The ability of a plant cell to give rise to a whole plant is called totipotency. The culture of a cell or a tissue in a suitable medium to produce new plan

What is folic acid, What is folic acid? Why is the anemia caused by deficie...

What is folic acid? Why is the anemia caused by deficiency of folic acid known as megaloblastic anemia? The folic acid (when ionized it is known as folate) is a coenzyme that

Mrna levels and rna species, You are working at a large, well funded resear...

You are working at a large, well funded research institute with the latest biochemical techniques available. The focus of your research is to find a specific mutation, or set of mu

What do you mean by blackcaps, Q. What do you mean by Blackcaps? Blackc...

Q. What do you mean by Blackcaps? Blackcaps are small songbirds found throughout Europe. A large population of blackcaps inhabits the forests of Germany. These blackcaps have t

Explain the surgical management for obesity, Explain the Surgical Managemen...

Explain the Surgical Management for Obesity? Surgical procedures are generally restricted for the morbidly obese persons. If an individual has a BMI of 40 or higher, or a BMI o

What is the importance of vitamin k, What is the Importance of Vitamin K ...

What is the Importance of Vitamin K The site of action of vitamin K activity is the highly complex mechanism of blood coagulation. Due to its effect on prothrombin, vitamin K i

What are the main structures within the cell nucleus, What are the main str...

What are the main structures within the cell nucleus? Within the cell nucleus the major structures are: the nucleolus, an optically dense region, spherical shaped, where there

Explain main functions of organic molecules for living being, What are the ...

What are the major functions of the organic molecules for living beings? Organic molecules, such as proteins, lipids and carbohydrates, perform numerous functions for living or

What is the diffusion, Q What is the diffusion? Diffusion is the spread...

Q What is the diffusion? Diffusion is the spreading of substance molecules from a region where the substance is further more concentrated to another region where it is less con

Explain the secondary structure of proteins, Explain the Secondary structur...

Explain the Secondary structure of proteins The secondary structure of a protein involves the way that the chain of amino acid either twists or folds back upon itself to form a

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