Chapter 2 - Neurons and Glia Flashcards
Cell theory
All tissue is composed of microscopic units called cells.
functions of glia
- insulates
- supports
- nourishes neurons
- aids in neuronal communication
functions of neurons
- process information
- sense environmental changes
- communicate changes to other neurons
- command body response
_____ discovered the Nissl stain
Franz Nissl
Where are nissl bodies located?
eER
the microscopic study of tissue structure
histology
- stains eER in cell body and dendrites
- facilitates the study of cytoarchitecture in the CNS
The Nissl Stain
central region containing the nucleus
perikaryon
What is the relationship between Nissl bodies and rER?
they’re the same thing, just different names.
soma
cell body
neurites
axons, dendrites
single neurite
- fast
- escape behaviour
- single processes (invertebrate)
- specialized segments
unipolar
two neurites
- dendrites carry information to cells
- axon transmits it to other cells
- specalized segments
Bipolar
more than two neurites
- dominate vertebrate nervous system
- given text book example of what neurons look like
- motor neurons
- complex cells (some will be myelinated)
multipolar
star-shaped neurons
stellate cell
pyramid-shaped neurons
pyramidal cells
what do spines do?
isolate chemical signals and are morphologically active events triggered by synaptic activation.
- each spine synapses with different cells
- these spines can change with regard to time
- these processes are believed to be the foundation of memory
- these changes that occur in neurons that allow for communication with other cells
- estrous cycle will change these
- complexity of cognition and behaviour - cells constantly changing.
nerves that transmit sensory information
primary sensory neurons
a nerve cell forming part of a pathway along which impulses pass from the brain or spinal cord to a muscle or gland.
- interacts with the peripheral system
motor neurons
a neuron that transmits impulses between other neurons, especially as part of a reflex arc.
interneurons
type of glial cell concerned with the production of myelin in the central nervous system
Oligodendrocyte
type of glial cell found in the peripheral nervous system.
- wrap around axon and nerons in different ways (entirely)
- insulate axons; speed action potential conduction
Shwann cells
type of glial cell. Most numerous glia in the brain.
- influence neurite growth
- regulate chemical content of extracellular space
- remove substances
- release substances
- supple metabolic substrate
- response to immune challenges (fighters)
- implicated in supporting normal function and responding to neurons
- release chemical signals that cell axons where to grow (growth factors)
- monitor extracellular environment (act like sponges)
astrocytes
the myelinating glia cells
Oligodendroglia (in CNA) Schwann cells (in PNS)