Anatomy 101: Glossary


Adult stem cell

Refers to stem cells derived from adults, but also to stem cells derived from fetuses.

Astrocytes

A type of glial cell that has many functions, on of which is to create a scar around the injury site

Axon

Part of a nerve cell, messages are sent along this long projection which makes contact with other neurons

Biopolymer

Man-made microscopic structure built with organic molecules like carbon

CNS

Central nervous system, brain and spinal cord

Cortex

Part of the brain involved in higher order thought processing (see figure)

Corticospinal tract

A bundle of axons going from the brain through the spinal cord that, in humans, carries information on movement; has a specific location in the spinal cord

Cytokine

Powerful chemical substances secreted by cells, these proteins are often involved in immune function

Dendrite

Projections from a nerves cell's body that receive information from other cells

Differentiated

A cell that has developed into a particular cell type, e.g. a neuron or heart muscle cell.

Dorsal roots

Nerve fibers that come into the spinal cord from the body and send sensory information to the brain

Embryonic stem cells

Stem cells derived from blastocysts (early embryos).

Endogenous

Originating within the organism, here meaning the regeneration that would happen without intervention

Enzyme

A protein that changes a chemical reaction, but is not changed itself

Epidural

On the surface of the spinal cord

Genes

A segment of DNA that has information to creation specific enzyme or protein

Glia

Nervous system support cells; make up approximately 90% of nervous system cells

Gray matter

Inner part of the spinal cord, looks grey because of the cell bodies located in that area

Growth cone

Tip of a regenerating axon

Hippocampus

Part of the brain critical for learning and memory

Kinase

An enzyme that is important in regulating cell functions, specifically can transfer a phosphate from a high energy phosphate such as ATP

Knock - in

Transgenic animal in which a gene has been added, or the process of adding a gene

Knock - out

Transgenic animal in which a gene has been removed, or the process of deleting a gene

Macrophages

Modulate the inflammatory response and stimulate the immune system; are a critical part of the body's response to injury

Morphology

The form and structure of an organism

Motoneurons

Neurons that make contact with and send messages directly to muscles

Multipotent stem cells

Multipotent cells can only become some types of cells, for example nervous system or muscle.

Myelin

Fatty substance that provides insulation in the CNS, wraps around axons to allow for electrical conduction

Neural plasticity

Ability of the brain, spinal cord and neurons to adapt to change, as when changes are seen in these structures after learning or injury

Neurogenesis

The process of forming new nerve cells. Neurogenesis occurs through the process of cell division.

Neuron / nerve cell

A cell that send electrical and chemical signals from one part of the body to another

Nogo

A small protein that prevents nerve cells from regrowing after injury, called an inhibitory molecule

OEGs

Olfactory ensheathing glia, or OEGs, are cells that aid in the regeneration of smell neurons, the only adult neurons we know of that regenerate as part of normal functioning

Oligodendrocytes

Glial cells that wrap around axons in the CNS and create insulating myelin

Pluripotent stem cells

Pluripotent cells can become many types of cells but not all types of cells.

PNS

Peripheral nervous system, the nervous system of the body

Progenitor cells

A cell that, upon dividing, gives rise to a particular type of cell, for example, oligodendrocyte progenitor cells give rise to oligodendrocytes.

Protein

Proteins are required for the structure, function, and regulation of the body's cells, tissues, and organs; and each protein has unique functions

Schwann Cells

Neuronal insulation makers of the peripheral nervous system, myelin makers of the PNS

Secondary degeneration

Tissue damage that occurs in the hours/days after injury; thought to be in part mediated by the immune response

Spinal tracts -- ascending and descending

Bundles of nerves the go through the spinal cord from the body delivering sensory information to the brain, ascending, or from the brain delivering motor information to the body, descending

Stem cells

Young cells that have the capacity to become other cell types

Totipotent stem cells

Totipotent cells can become all types of cells.

Transgenic models

Genetic manipulation of an animal's genes, usually mice

Undifferentiated

A cell that has not yet developed into the type of cell it will eventually be. An un-differentiated cell may be able to develop into different cell types (that is, it may be a stem cell), or its fate may already be determined (lineage restricted).

Ventral roots

Nerve fibers that come out of the spinal cord into the body and send motor information to muscles

White matter

Outer part of the spinal cord, looks white because of the myelinated (a white fatty substance that wraps axons) spinal tracts running through this area