In this case, the damper is normally opened by the force of the spring but can be closed by the force of the motor. Removal of electrical power re-opens the damper. This style of damper is advantageous because it is fail safe; if the control to the damper fails, the damper opens and allows air to flow.
The adrenal glands, located on the top of each kidney, are responsible for releasing different hormones. Adrenal gland disorders occur when the adrenal glands produce too much or too little of these hormones.
The cortex and the medulla have very separate roles within the adrenal glands, although there is some interaction between them. There are three roles that the cortex typically performs. This occurs in the innermost layer of the cortex, the zona reticularis.