ANATOMY

Detailed explanation-1: -The vertebrate brain contains hundreds of distinguishable nuclei, varying widely in shape and size. A nucleus may itself have a complex internal structure, with multiple types of neurons arranged in clumps (subnuclei) or layers.

Detailed explanation-2: -Weighing about 3 pounds in the average adult, the brain is about 60% fat. The remaining 40% is a combination of water, protein, carbohydrates and salts. The brain itself is a not a muscle. It contains blood vessels and nerves, including neurons and glial cells.

Detailed explanation-3: -The region of the neuron containing the nucleus is known as the cell body, soma, or perikaryon (Figure 8.2). The cell body is the metabolic center of the neuron.

Detailed explanation-4: -The central nervous system (which includes the brain and spinal cord) is made up of two basic types of cells: neurons (1) and glia (4) & (6). Glia outnumber neurons in some parts of the brain, but neurons are the key players in the brain.