GROUP I Pituitary “The master gland”
Dec 26, 2015
Main points :-1-Name & location.2-Structure.3-pituitary in vertebrates.4-How does it work?5-The glands’ hormones & their function.6-Disorders of pituitary.
1-Name & location.-Pituitary gland is also called the hypophysis.It lies in a small cavity in the skull called
hypophysial fossa below the brain as shown:
2-Structure.Pituitary is divided into 2 parts : 1- Anterior one which is glandular or
adenohypophysis located toward the front of the head
2- Posterior one which is neural or neurohypophysis located toward the back of the head.
3-pituitary in vertebrates.In lower vertebrates there is an intermediate lobe
between the anterior & the posterior ones , this lobe has an endocrine function.
In higher vertebrates there is no intermediate lobe but cells with no endocrine function.
As shown, the anterior pituitary secretion is under the control of hypothalamus through the following hormones: GRH , GIH , TRH , CRH , GnRH , PRH & PIH .
Pituitary disorders
As compared with the hand of a typical person (left), the hand of a patient with acromegaly (right) is enlarged, the fingers are widened, thickened and stubby, and the soft tissue is thickened
Teeth showing classic teeth gapping due to acromegaly on lower jaw
Figure 1 A 22-year-old man with gigantism due to excess growth hormone is shown to the left of his identical twin. The increased height (Panel A) and enlarged hand (Panel B) and foot (Panel C) of the affected twin are apparent. Their height and features began to diverge at the age of approximately 13 years.
Have a look for more information & figures : http://www.tjhsst.edu/~jleaf/disability/jweb/JWEB.HTM