Arteries: A blood vessel that carries blood away from the heart to the rest of the body.

Axons: Part of a nerve cell that carries impulses away from the cell body to the next neuron, muscle cell or gland.

Blood Vessel: Any artery, vein or capillary through which blood flows.

Bone: A connective tissue composed of cells embedded in a matrix of ground substance, inorganic salts, and collagenous fibers.

Cardiac Muscle: The muscle of the heart

Cartilage: A specialized type of connective tissue that provides support and aids movement at joints.

Cell: The smallest independent unit of life; the component of tissues

Cell Nucleus: The central part of the cell that contains the chromosomes which are the genetic material for the cell.

Cerebellum: The second largest part of the brain. It refines and coordinates muscular movements.

Cerebrum: The upper main part of the brain consisting of right and left hemispheres. Controls conscious and voluntary processes

Chondrocyte: A non dividing cartilage cell embedded in small cavities within the matrix of cartilage connective tissue.

Connective Tissue: Binds together and supports other tissues and organs. It includes various kinds of fibrous tissue, fat, bone and cartilage.

Dendrites: Short thread like branches of a nerve cell that carries impulses toward the cell body.

Diaphragm: a muscle found at the bottom of the rib cage. When it contracts (shortens) it increases the size of the chest cavity pulling in air.

Emphysema: The loss of elasticity or the destruction of lung tissue. Lungs are unable to fully contract causing air to be left in the lungs.

Epithelial Tissue: Groups of cells that cover or line external body surfaces (skin) or internal body surfaces such as hollow organs, and vessels. These tissues often contain cells that secrete substances that lubricate or take part in chemical reactions.

Esophagus: A muscular, membranous tube through which food passes from the throat into the stomach.

Fluid Matrix: A fluid non-living intercellular substance in which living cells are embedded. Part of connective tissue.

Gray Matter: Grayish nerve tissue of the brain and spinal cord consisting chiefly of nerve cells.

Hemorrhage: The rapid loss of blood from a blood vessel.

Liver: a reddish wedge shaped organ which weighs about 3 pounds in the average adult. It modifies nutrients to make them useable by body tissue.

Lumen: The passage within a hollow tubular organ.

Mitochondria: A part of a cell (organelle) found in the cell's cytoplasm which produces most of the energy for the cell.

Muscle: See muscle tissue

Muscle Tissue: A collection of muscle fibers that can contract and relax to move body parts. Examples include cardiac (heart) muscle, skeletal muscle (in limbs, trunk, jaw and face) and smooth muscle (in digestive tract, eyes, blood vessels and ducts).

Nervous Tissue: A collection of cells which respond to stimuli and transmit electrical impulses or messages. Examples include: brain, spinal cord and nerves.

Neurons: A cell specialized to transmit impulses.

Pancreas: pinkish gray gland about 6 inches long that secretes hormones into the blood stream and enzymes into the small intestine.

Scar Tissue: The dense fibrous tissue replacing normal tissues destroyed by injury or disease.

Sinus Cavity: air cavities in the skull that act as resonating chambers for the voice and lighten the weight of the skull bones.

Tendon: A strong cord of fibrous connective tissue that attaches muscle to the bone.

Tissue: A population of many similar cells that perform a specific function; categorized into four types: epithelial, nervous, muscle and connective.

Vertebrae: Twenty six separate bones which make up the spine. Creating strong but flexible support for the neck and trunk

White Matter: Whitish nerve tissue of the brain and spinal cord consisting chiefly of nerve fibers.