Zoology - Chemical Coordination and Integration Question with Solution | TestHub
As part of a student project, Sheela surgically made a full cut in the hypothalamo-hypophyseal tract (infundibulum) in pregnant rabbits and studied the physiological effect on different tissues/organs. Which of the following should be expected?
(i) Formation of a large volume of dilute urine
(ii) Increased blood sugar levels
(iii) Increased heart rate
(iv) Difficulty in parturition
Options:
Answer:
Solution:
Pituitary gland is the master endocrine gland of the body. It is connected to hypothalamus which is a part of the forebrain. Hypothalamus controls the pituitary gland and thus it is known as Master of master endocrine gland. Pituitary gland consists of two lobes: Adenohypophysis and Neurohypophysis. Neurohypophysis is also known as posterior pituitary and it is connected to the hypothalamus through infundibulum or pituitary stalk. Hypothalamic nuclei secretes two hormones which are stored in the posterior pituitary in hassall's corpuscles. These two hormones are ADH and Oxytocin. Hence if the stalk is cut these two hormones will not be stored in the posterior part and thus will not be able to perform its function. If ADH secretion decreases, water reabsorption will be affected and thus dilute urine will be formed. Oxytocin is the birth hormone as it plays an important role during parturition and milk production. In the question the rabbit is pregnant and hence if the infundibulum is cut there will be no oxytocin release and this will affect parturition.
