Phases of ovarian cycle, Biology

Assignment Help:

Phases of Ovarian Cycle

In non-mammalian vertebrates the ovarian cycle consists of the following phase;

  1. Pre breeding phase
  2. Breeding phase and
  3. Post breeding phase.

During pre breeding phase growth and differentiation of the ovarian follicles takes place. The follicles start accumulating yolk and at the end of this phase the follicles are ready for ovulation and fertilisation. Breeding phase is the period of ovulation, mating and fertilisation. This phase is followed by the post breeding phase in which ovary contains the spent follicles, or postovulatory follicles (the follicles from which the ovum is expelled during ovulation), some follicles which failed to ovulate, and atretic follicles. Degeneration and disintegration of postovulatory and atretic follicles also take place during post breeding phase.

In some of the animals there is a resting phase in which no gametoganic activity takes place. All the germ cells are at rest for some time before entering into the follicular or the pre-breeding phase. In the male animals testicular activity is a continuous process. Spermatogenesis takes place throughout the year, but spermiation (release of sperms) parallels with the ovulatory phase of the females. The reproductive cycles are regulated by-ho-pones from the pituitary and the gonads. Apart from the endogenous mechanisms, external stimuli also effect the gonadal activity.


Related Discussions:- Phases of ovarian cycle

Mollusca, Order of classification

Order of classification

Explain angio-edema, Explain Angio-edema Angio-edema:  Swelling of the ...

Explain Angio-edema Angio-edema:  Swelling of the mucous membranes, tissues beneath the skin or an internal organ because of an allergic reaction.

Explain casein, Explain Casein Casein is an important example of protei...

Explain Casein Casein is an important example of protein, which can be boiled without apparent change in stability. The exceptional stability of casein makes it possible to boi

Difference between plants and animals, DIFFERENCE BETWEEN PLANTS  AND ANIM...

DIFFERENCE BETWEEN PLANTS  AND ANIMALS - S . N o . C h a ra c ter P l an ts A n i m al s 1 Nutrition

Which amino acid can form disulfide bonds, a. Which amino acid can form dis...

a. Which amino acid can form disulfide bonds? b. Which level of protein structure do disulfide bonds affect? How? c. Cytoplasmic proteins rarely form disulfide bonds, even if they

Membrane perforation of sinus graft surgery, Membrane Perforation of sinus ...

Membrane Perforation of sinus graft surgery it is the most common complication during the sinus graft surgery resulting from the scoring of lateral access window for surgery an

Dissolved gases and alkalinity, Dissolved Gases and Alkalinity Disso...

Dissolved Gases and Alkalinity Dissolved Gases The marine environment serves as a gigantic reservoir of dissolved oxygen and carbon dioxide, which respectively help reg

Function of noradrenaline in consciousness, Q. Function of Noradrenaline in...

Q. Function of Noradrenaline in consciousness? Increased level of noradrenalin is implicated in wakefulness. Locus coeruleus noradrenergic neurons decrease their rate of firing

Are nematodes triploblastic or diploblastic animals, Q. Are nematodes tripl...

Q. Are nematodes triploblastic or diploblastic animals? Just like platyhelminthes, nematodes are triploblastics that is they present three germ layers (ectoderm, endoderm and m

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