Advertisements
Advertisements
Question
Long answer question
Explain the role of the hypothalamus and pituitary as a coordinated unit in maintaining homeostasis?
Advertisements
Solution
i. The hypothalamus controls the secretory activity of the pituitary gland (anterior pituitary) by producing, releasing, and inhibiting hormones.
ii. Anterior pituitary and intermediate lobes are connected to the hypothalamus through the hypophyseal portal system. Various hormones secreted by the hypothalamus reach the pituitary gland through the hypophyseal portal system.
iii. The portal vein collects blood from various parts of the hypothalamus and opens into the anterior lobe of the pituitary. From the pituitary, the vein finally carries the blood into the superior vena cava. It helps in the feedback mechanism for hormonal control.
iv. Also, a negative feedback mechanism takes place in the form of hormones released by the target glands to decrease the secretion of the pituitary gland.
v. In such a negative feedback mechanism, the secretion of ACTH, TSH, and gonadotropins (FSH and LH) decreases when their target gland hormone levels rise.
e.g. Adrenocorticotropic hormone (ACTH) stimulates the cortex of the adrenal gland to secrete glucocorticoids, mainly cortisol. In turn, an elevated blood level of cortisol decreases secretion of both corticotropin and corticotropin-releasing hormone (CRH) by suppressing the activity of the anterior pituitary corticotrophs and neurosecretory cells.
APPEARS IN
RELATED QUESTIONS
Briefly mention the mechanism of action of FSH.
Given below are two diagram (one is correct the other is some hwat incorrect) showing the transport of a hormone from its source gland/ cell to the target organ/ cell.
Which one has the error A or B ?
The deficiency of ADH causes:
List some of the functions of pituitary gland.
Give the Technical Term: Name the glands which secrete the following hormone: ACTH
Short answer question
Where is the pituitary gland located? Enlist the hormones secreted by the anterior pituitary.
Which endocrine gland is also known as ‘master gland’?
Mention if the following statement is true (T) or false (F). If false, rewrite the correct word (not words) striking out the single wrong one.
Pituitary is of the size of a lemon.
Write the full for of ACTH.
The diagram given alongside shows an endocrine gland in the human body. Study the diagram and answer the following questions:
 |
- Identify the gland. Write its specific location in the human body.
- Label the guidelines 1, 2 and 3 shown in the figure.
- Name any two secretions from part 1 and two from part 2.
- The deficiency of which hormone causes Diabetes insipidus? How is this condition different from Diabetes mellitus with respect to the abnormal substances present in the of urine.
