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

How does hcl also directly participate in digestion, Besides being fundamen...

Besides being fundamental for the activation of the main gastric digestive enzyme how does HCl also directly participate in digestion? With its corrosive effect, HCl also helps

Nonsurgical retreatment -secondary endodontic ttt, Nonsurgical retreatment ...

Nonsurgical retreatment (secondary endodontic ttt ) -Is the main difference between primary endodontic disease versus post treatment disease is the need to Regain access to

What is malnutrition, What is malnutrition? Malnutrition can be defined...

What is malnutrition? Malnutrition can be defined as a pathological condition resulting from a relative or absolute deficiency or excess of one or more of the essential nutrien

Define mechanism of rotary instrument fracture, Define Mechanism of Rotary ...

Define Mechanism of Rotary Instrument Fracture - Cyclic Fatigue Occurs unexpectedly and without any visible signs of plastic deformation o An instrument rotating freely in a cu

Theory or principle of determination of the quality of milk, Explain the Th...

Explain the Theory or Principle of Determination of the Quality of Milk Milk is an ideal medium for the survival and growth of microorganisms. It contain all the nutrients, i.e

Bacteria - type of microorganisms, Q. Bacteria - type of microorganisms? ...

Q. Bacteria - type of microorganisms? Many of us know bacteria only as "germs," invisible to naked eyes that can invade our bodies and make us sick. Few know that many bacteria

Describe about the anemia and its type, Q. What is the anemia? What are the...

Q. What is the anemia? What are the four major types of anemia? Anemia is low concentration of hemoglobin in the blood, the four major kind of anemia are the nutrient-deficienc

Determine the implant failure after abutment connection, After Abutment Con...

After Abutment Connection The patient may complain of pain during screw tightening. Any clinical evidence should be looked into. It is important not to overtighten and overtorq

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