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Behavioral Neuro
Ch.2 nerve cell definitions
Term | Definition |
---|---|
Soma | cell body contains the nucleus and much of the machinery that provides for the life processes of the cell |
Dendrites | the receiver's of communication from other neurons |
axon | long slender tube, often covered by a myelin sheath. The outer surface of the axon carries information from the cell body to the terminal buttons and functions much like an electrical cord. |
Terminal Buttons | at the end of the axon, opposite the soma, the branches end in little knobs |
neurotransmitter | when the action potential reaches the terminal buttons they secrete a chemical that either excites or inhibits the receiving cell |
axoplasmic transport | active process that propels substances along microtubule "tracks" that run inside the length of the axon |
anterograde axoplasmic transport | movement from the soma to the terminal buttons "toward the front" *this type of transport is accomplished by molecules of a protein called kinesin |
kinesin | molecule which resemble a pair of legs and feet, attach themselves to the item being transported down the axon |
dynein | carry substances from the terminal buttons to the soma |
retrograde axoplasmic transport | reverse direction in which dynein carry substances from the terminal buttons to the soma (about half as fast as anterograde |
membrane | the boundry of the neuron and consists of a double layer of lipid (fat like) molecules |
cytoskeleton | gives neurons its shape, the interior of neurons contains a matrix of strands of protein. |
microtubules | bundles of thirteen protein filaments arranged around a hollow core. Also, the thickest of the protein strands |
cytoplasm | jellylike, semiliquid substance that fills the space outlined by the membrane. |
organelle | "little organ" small specialized structures (just as the body contains organs) in cytoplasm |
nucleus | round or oval structure found in the soma which is enclosed by the nuclear membrane. *nucleolus and chromosomes reside inside the nucleus |
nucleolus | responsible for the production of ribosomes. |
ribosomes | small structures that are involved in protein synthesis |
DNA (deoxyribonucleic acid) | contain the organism's genetic information. Cannot leave the nucleus. |
chromosomes | consist of long strands of DNA |
mRNA | messenger ribonucleic acid, which receives a copy of the information stored at that location, it then leaves the nuclear membrane and attaches to ribosomes |
transcription | DNA is transcribed to mRNA so that it is portable |
translation | the ribosomes use the information from the mRNA and create proteins |
enzymes | direct the chemical processes of a cell by controlling chemical reactions |
endomembrane system | network of internal membranes composed of endoplasmic reticulum, Golgi apparatus and lysosomes |
endoplasmic reticulum | 2 forms-rough, smooth. Rough-contains ribosomes is used to be transported out of the cell. Smooth- provides channels forthe segregation of molecules involved in various cellular process. |
Lipid | fat molecule |
Golgi apparatus | special form of smooth endoplasmic reticulum. Serves as a wrapping or packaging agent such as the wrapping of secretory cells that release hormones to keep from releasing the hormones at the wrong time |
exocytosis | membrane-wrapped product migrates tot the inside of the outer membrane of the cell, fuses with membrane, and bursts, spilling its contents into the fluid surrounding the cell |
Glia | they insulate neurons from one another so that neural messages do not get scrambled, they also destroy and remove the carcasses of neurons that are killed by disease or injury. |
microglia | like some types of astrocytes they act as phagocytes, engulfing and breaking down dead and dying neurons, but in aqddition they serve as one of the representatives of the immune system in the brain, protecting the brain from microorganisms |