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 theory of law of minimum, Explain the theory of Law of Minimum ...

Explain the theory of Law of Minimum    This is one of the earliest hypotheses put forward by von Liebig on the relationship between the amount of plant  nutrient in the soil a

Define transport proteins in plasma, Define Transport Proteins in Plasma? ...

Define Transport Proteins in Plasma? Transport proteins, embedded in lipid membranes, make easy the import of nutrients into cells or the release of toxic products into the sur

Cancer lung, Cancer Lung Incidence of cancer lung is more in persons ...

Cancer Lung Incidence of cancer lung is more in persons who smoke. Environmental and industrial pollution is also a risk factor in the increase in incidence. Clinic

Caryopsis - development of fruit, Caryopsis - Development of Fruit In ...

Caryopsis - Development of Fruit In cereals each carpel has one ovule and therefore the mature fruit has, just one seed. During maturation, very little or no cell divisions ar

Illustrate erythropoietin, Define Erythropoietin A. acts by stimulating...

Define Erythropoietin A. acts by stimulating the production of red blood cells by the peritubular interstitial cells of the kidney cortex. B. is secreted by cells in the bon

How to do glucose test, How to do Glucose test A glucose test is a type...

How to do Glucose test A glucose test is a type of blood test used to determine the amount of glucose in the blood. There are several different kinds of glucose tests:  "

Estimation of protein by growth and body, Define Estimation of Protein by G...

Define Estimation of Protein by Growth and body, weight changes? The methods under this category include Protein efficiency ratio (PER) Net protein ratio (NPR)

Why is pattern baldness more common in men than in women, Why is pattern ba...

Why is pattern baldness more common in men than in women? Pattern baldness is handled by the allele B. Testosterone interacts with the heterozygous genotype (BB′) to make baldn

Limerick, how do we write a limerick spell?

how do we write a limerick spell?

ACTINOMYCETES, WHAT ARE THE DIFFERENT CULTURE MEDIAS USED FOR ISOLATION OF ...

WHAT ARE THE DIFFERENT CULTURE MEDIAS USED FOR ISOLATION OF ACTINOMYCETES?

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