Answer to Question 1
The pituitary gland is the pea-sized master gland at the base of the brain. Like the adrenal gland, it is a structure with two glandular regions with separate functions. It is divided into an anterior and a posterior region rather than an inner and outer region as the adrenal gland is.
Answer to Question 2
The primary command center for the endocrine's stress response is in the hypothalamus, and one of its primary target organs is the adrenal gland. By transmitting signals through the brain stem's nucleus of the solitary tract into pre-ganglionic fibers of the sympathetic nervous system directly to the adrenal medulla, the paraventricular nucleus of the hypothalamus has a strong influence over this region of the adrenals. This sympathetic-adrenal medulla axis (SAM) forms one of the primary systems of the fight-or-flight response.
Structure of fish gills.
Schematic of de novo structure prediction using Rosetta
Structure of cytochrome c oxidase (complex IV)
Structure of a Tooth
Gene structure