The annular ligament stabilizes the proximal radius against the ulna during pronation and supination of the wrist. The ligament is located deep to the supinator and origin of the extensor muscles of the forearm near the head and proximal shaft of the radius at the elbow.

The cell is the basic building block of all living things. Cells are organized into tissues having specialized properties and functions. Tissues are further organized into organs (and organ systems).

The cerebral cortex is the largest part of the brain and plays a key role in awareness, communication, consciousness and memory.

When the body is exposed to prolonged heat, more blood is shunted to superficial veins in order to lower body temperature. This results in decreased venous return to the heart. The resulting lowered cardiac output causes less oxygenated blood to reach the brain, causing dizziness and fainting.

Neutrophils, basophils and eosinophils are the three types of granular leukocytes (white blood cells) of the immune system which consume infectious diseases and foreign materials.