Chapter 23, Problem 1CC

Summary Introduction

To determine: The two parts of the adrenal gland and their respective hormonal secretions.

Introduction: Loop of Henle is the countercurrent multiplier of kidneys. It increases the osmolarity of interstitial fluid by actively moving the ions out of the nephron. This increase in osmolarity is important for forming concentrated urine.

Explanation of Solution

The adrenal cortex is a complex organ which secretes several hormones. It is divided into two parts. The two parts are as follows:

• Adrenal medulla:

  This part of adrenal gland occupies a small space in the inner mass. It covers a little more than one-fourth of the organ. It is made up of modified sympathetic ganglia. These ganglia are responsible for the secretion of catecholamines (majorly epinephrine). Catecholamines control the compensatory mechanism of fight or flight situation.

• Adrenal cortex:

  This part of the adrenal gland covers the remaining area. It occupies the outer three-fourth portion of the gland. It is responsible for the secretion of different types of steroid hormones. These hormones include mineralocorticoids, glucocorticoids, and sex hormones.

Conclusion

The two parts of the adrenal gland are adrenal medulla and adrenal cortex. The hormones secreted by the adrenal medulla are catecholamines and by the adrenal cortex are steroid hormones.