Pituitary gland, Biology

Assignment Help:

PITUITARY GLAND (HYPOPHYSIS CEREBRI) -

  • It develops from ectoderm of the embryo.
  • The pituitary gland is located just below the hypothalamus. The pituitary gland is situated in a depression the sella turcica of sphenoid bone of the skull.
  • The pituitary gland is the smallest endocrine gland. It is about 1.3 cm in diameter and weighs about half a gram.
  • The gland is attached to the brain by a stalk the infundibulum which is continuous with the hypothalamus above.
  • Adenohypophysis or pars distalis and the posterior lobe or neurohypophysis or pars nervosa.
  • Adenohypophysis originates as Rathke's pouch from dorsal wall of stomodaeum in the embryo, but later its connection with the stomodaeum disappears.
  • The neurohypophysis originates as an outgrowth from the floor of the diencephalon.
  • A third lobe, called the intermediate lobe or pars intermedia is a part of adenohypophysis.

1108_pituitary gland.png

  • Adenohypophysis comprises about 75% part of the pituitary gland.
  • The hypophysial portal veins carry blood containing neurohormones (releasing factors) from the hypothalamus to tbe adenohypophysis.
  • Neurohypophysis comprises about 25% part of the pituitary gland. The axons of neurosecretory cells (secretory neurons) extend into the neurohypophysis where these axons terminate as axon terminals. These terminals are embedded in a neuroglial tissue formed of large and branched cells called pituicytes.
  • No hormones are synthesized in neurohypophysis but two hormones, synthesized in the hypothalamic neurosecretory cells remain stored in very small vesicles in the axons and terminals. These vesicles are called Herring bodies.

Related Discussions:- Pituitary gland

Lntracardiac hemodynamics, Provides one dimensional ("ice pick") view of...

Provides one dimensional ("ice pick") view of the heart only provides information with respect to the distance of each object from the transducer and no information in the l

What do you know about vascular access, Q. What do you know about Vascular ...

Q. What do you know about Vascular Access ? Femoral and brachial arteries are still the commonest routes of access for aortography. Thoracic Aorta A sound knowledge of

Define the skin capillary fragility test, Define the Skin Capillary Fragili...

Define the Skin Capillary Fragility Test? One of the earliest signs of ascorbic acid deficiency is the fragility of the capillaries. Capillary fragility is measured by applyin

Kind of tetrasporic embruo sac, what are the kinds of tetrasporic embryo sa...

what are the kinds of tetrasporic embryo sac...detail information

Cortex, Cortex  can be described as follows 1) The outer part of the org...

Cortex  can be described as follows 1) The outer part of the organ, such as, the adrenal cortex, which produces many steroidhormones;  2) in plants, the area of the stem or root

How vaginal infections cause, How Vaginal infections cause Sulfonamide ...

How Vaginal infections cause Sulfonamide creams, other ''broad-spectrum'' vaginal preparations, and currently available preparations of Lactobacillus  species or dairy products

Treatment and nursing management of cleft lip, Treatment and Nursing Manage...

Treatment and Nursing Management The initial treatment is surgical repair of  the cleft. The timing of the repair varies from surgeon to surgeon, but most prefer cleft lip rep

Excretion, What is the excretion for agamalizard

What is the excretion for agamalizard

What is combination therapy, What is Combination therapy Combination th...

What is Combination therapy Combination therapy - Use of combination therapy for treatment of immunosuppressed patients with invasive aspergillosis (IA), which has a high morbi

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