Unit 2.1 - Function & Components of the Nervous System Flashcards
What is the function of the nervous system?
- receive info
- integrate info
- transduce info
What is the Central Nervous System made up of?
- brain
- spinal cord
What is the Peripheral Nervous System made up of?
sensory (afferent) and motor (efferent) neurons
What are the 2 basic kinds of cells found in the nervous system?
- neurons
- glial cells
What is the function of the neuron?
to generate and transmit electrical impulses over long distances
What are the 4 main parts of the neuron?
- soma (cell body)
- dendrites
- axon
- axon terminal
Clusters of cell bodies in the CNS is knows as ____ while clusters of cell bodies in the PNS is known as ____
CNS: nuclei
PNS: ganglia
TRUE OR FALSE:
Dendrites transfer electrical signals away from the soma and axons transfer electrical signals toward the soma
FALSE:
Dendrites = TOWARDS soma
Axon = AWAY FROM soma
What are bundles of axons in the CNS and PNS called?
CNS = tracts
PNS = nerves
Classify neurons by structure:
Pseudounipolar
- somatic sensory neurons (afferent)
Bipolar
- smell/vision sensory neurons
Anaxonic
- no apparent axon
Multipolar - CNS
- highly branched, lots of dendrites
- lack long extensions
Multipolar - Efferent
- 5 to 7 dendrites
- single long axon
In which neuron does the axon fuse to the dendrites during development?
pseudounipolar
Which neurons make up 96% of all neurons? Where are they located?
Interneurons, located inside the CNS
Where are the cells bodies of the efferent motor neurons located?
Within the CNS, cytoplasmic extensions transmit info to effectors
How do glial cells contribute to the function of the neurons?
- aid in nerve impulse conduction
- maintain microenvironment around the neurons
Name the different PNS glial cells and their functions:
schwann cells
- forms myelin on part of the axon, secrete neurotrophic factors
satellite cells
- non myelinating schwann cells
- support cell bodies
TRUE OR FALSE:
Gap junctions are found between layers of the myelin sheath
TRUE
What is the function of myelin sheath?
- acts as an electrical insulator
- allows for fast electrical transmission
What are the different types of CNS glial cells?
- oligodendrocytes
- microglia
- ependymal cells
- astrocytes
What is the function of oligodendrocytes?
wrap around axons and form myelin sheaths
- CNS version of schwann cells
This CNS glial cell is part of the blood brain barrier:
astrocytes
What is the function of astrocytes?
- transfer nutrients
- helps maintain homeostasis in extracellular fluid around neurons microenvironment
These CNS glial cells are immune cells that remove damaged cells and foreign invaders
microglia
These cells produce the cerebrospinal fluid (CSF) and create selectively permeable barriers between compartments
Ependymal cells
