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

Explain about the functional properties of proteins, Explain about the Func...

Explain about the Functional Properties of Proteins? It may be clear by now that functionality (as implied to food ingredients) refers to 'any property aside from the nutrition

Modification of trna, Transfer RNA molecules are notable for having general...

Transfer RNA molecules are notable for having generally nucleotides shown in the figure such as 1-methylguanosine (m1G), pseudouridine   (Ψ), dihydrouridine   (D), inosine (I) and

Explain the bioavailability of vitamin e, Explain the Bioavailability of Vi...

Explain the Bioavailability of Vitamin E? For dietary purposes, vitamin E activity is expressed as a-tocopherol equivalents (a-TEs). One α-TE is the activity of l mg α-tocophe

Determine the features of the nervous system of arthropods, What are the no...

What are the noteworthy features of the nervous system of arthropods? In arthropods the nervous system has more complicated sensory receptors with well-advanced cephalization.

What is dextrin, Dextrin  Polymers of D-glucose, formed due to partial ...

Dextrin  Polymers of D-glucose, formed due to partial  hydrolysis of starch by enzymes.

Define fermented dairy products-cheese, Normal 0 false false ...

Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4

Cephalisation - metazoa, Cephalisation - Metazoa Bilateral animals whe...

Cephalisation - Metazoa Bilateral animals when creeping or swimming, have a tendency to keep the same end of the body forward and the same surface down towards the substratum.

Characteristic of callus, Characteristic of Callus The most important ...

Characteristic of Callus The most important characteristic of callus from a functional view point is that abnormal growth has the potential to develop normal roots, shoots and

Severity of heat treatment for pasteurization depends on, Define on which s...

Define on which severity of heat treatment for pasteurization depends? The severity of heat treatment for pasteurization depends on: 1.  Heat resistance of target microorgan

Define the effect of niacin deficiency on digestive sysytem, Define the Eff...

Define the Effect of niacin deficiency on Digestive Sysytem? The predominant symptoms are glossitis and diarrhoea. Glossitis, cheilosis and stomatitis may vary from mild rednes

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