Endocrinology

[501]

Is the adrenal cortex more essential to the survival of an individual than the adrenal medulla?

[gen2]

They are both essential but in different ways.

The adrenal cortex produces corticoids and androgens
The glucocorticoids get their name from their effect of raising the level of blood sugar (glucose). One way they do this is by stimulating gluconeogenesis in the liver: the conversion of fat and protein into intermediate metabolites that are ultimately converted into glucose.
Cortisol and the other glucocorticoids also have a potent anti-inflammatory effect on the body. They depress the immune response.
Aldosterone acts on the kidney promoting the reabsorption of sodium ions (Na+) into the blood. Water follows the salt and this helps maintain normal blood pressure.
The adrenal cortex secretes precursors to androgens such as testosterone.

The adrenal medulla produces adrenaline and noradrenaline.
These trigger the Fight or Flight reaction.