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 the term - neurochemical manipulations, Explain the term - Neuroche...

Explain the term - Neurochemical Manipulations Neurochemical and immunological methods have been used to identify groups of neurons in the central nervous system that use speci

Explain the fluoride toxicity, Explain the Fluoride Toxicity? Fluoride ...

Explain the Fluoride Toxicity? Fluoride is a cumulative toxin. Ingestion of fluoride 1.0-1.5 mg/L for several years may produce dental fluorosis, i.e. browning and pitting of t

Determine the meaning of response cost, Determine the meaning of Response c...

Determine the meaning of Response cost This is a type of punishment in which the subject has to return back the token (positive reinforcement) earned earlier if the subject dis

Explain nutritive and non-nutritive sweeteners, Q. Explain Nutritive and No...

Q. Explain Nutritive and Non-Nutritive Sweeteners? Nutritive Sweeteners: We know some sweeteners like glucose, honey, molasses, fruit juice, dextrose, maltose, mannitol, sorbit

Regional specialisation, Regional Specialisation Regional specialisati...

Regional Specialisation Regional specialisation takes place usually by three processes – 1) Restriction of certain structures to a few segments, for example, gonads are res

Treatment of acute myocardial infarction, Q. Streptokinase is a substance u...

Q. Streptokinase is a substance used in the treatment of acute myocardial infarction. How does this substance act? Substances known as fibrinolytics, like urokinase and strepto

Epidemiological association between hemophilia and hiv, Q. What is the epid...

Q. What is the epidemiological association between hemophilia and HIV infection? In the past the blood banks did not usually perform HIV detection tests and many hemophilic pat

State the series of stimuli, State the series of stimuli ERPs a series ...

State the series of stimuli ERPs a series of stimuli such as tones or light flashes are presented to the participant, and the raw EEG for a precise one or two second period fol

What do you understand by hypelglycemia, Q. What do you understand by Hypel...

Q. What do you understand by Hypelglycemia? Hypelglycemia (abnormally high blood sugar): Maintenance of blood glucose levels within or close to the normal range has been stress

Six kingdom worksheet, what protist changes shape constantly and flows arou...

what protist changes shape constantly and flows around its food to engulf it?

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