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

Effects on health - consequences of air pollution, Effects on Health - Cons...

Effects on Health - Consequences of Air Pollution Since the air pollutants are inhaled they attack various parts of the respiratory system on their route to air sacs. Once the

What factors influence whether a person will develop cancer, What factors i...

What factors influence whether a person will develop cancer? Factors contain the person's age, number of exposures to carcinogens, amount of carcinogen in every exposure, and p

Define fuel molecules and lipogenesis, Define Fuel Molecules and Lipogenesi...

Define Fuel Molecules and Lipogenesis? Lipogenesis is a collective name for the complex process of producing lipids (fatty acids) from smaller precursor molecules. The synthesi

Explain cardiac prophylactic antibiotics, Cardiac Prophylactic antibiot...

Cardiac Prophylactic antibiotics can decrease the incidence of infection after cardiac surgery, and intraoperative redosing has been associated with adecreased risk of postoper

Successive changes in animal life during hydrosere, Successive Changes in A...

Successive Changes in Animal Life during Hydrosere The successive changes in plant communities in the different seral communities of a hydrosere. The question arises, is ther

Explain about colloidal system, Explain about colloidal system A colloi...

Explain about colloidal system A colloidal system, on the other hand, is a heterogeneous system. The material that forms the base of the system is called  the dispersion medium

What is the difference between taeniasis and cysticercosis, Q. What is the ...

Q. What is the difference between taeniasis and cysticercosis? The Taeniasis is the parasitic disease caused by the adult tapeworm installed within the human intestine. The

Formation of the amino acids sequences of a protein, Q. How do nucleotides ...

Q. How do nucleotides of mRNA chains encode information for the formation of the amino acids sequences of a protein? There are only four types of nitrogen- containing bases tha

Explain about thiol proteases, Explain about thiol proteases Group of  ...

Explain about thiol proteases Group of  thiol proteases, similar in structure to each other, are found in plants. These include  papain from the papaya fruit and  ficain from f

How age factors affecting the calcium absorption, How Age factors Affecting...

How Age factors Affecting the calcium absorption? Age is another factor which influences the absorption of calcium. Fractional absorption of calcium is highest in infancy i.e.,

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