Lecture 2 Flashcards
What is the importance of the nervous system?
- master control/communicator in the body
- every thought, action, emotion reflects its activity
- all body systems (both voluntary/involuntary) are controlled by it
What are the three functional classifications of the nervous system?
- input: through millions of sensory receptors tha tmonitor changes/stimuli inside/outside the body
- integration: processes and interprets the sensory input and decides what to do at each moment
- output: effects or causes a response by activating muscles or glands (effectors) via motor output
What are the two structural classifications of the nervous system?
Central NS and Peripheral NS
What are the functional classifications of the PNS?
Sensory/afferent:
- somatic fibers
- visceral fibers
Motor/efferent:
- somatic NS (voluntary)
- autonomic NS (involuntary): sympathetic NS, parasympathetic NS
What are the organs involved in the CNS and PNS?
CNS: brain, spinal cord, encased in bone
PNS: cranial nerves, spinal nerves, peripheral ganglia
What is the cortex?
outer layer of the brain
What are some anatomical directions?
Anterior: toward head
Posterior: toward tail
Rostral/cranial: toward the front of the face
caudal: away from front of the face
dorsal: top and back of head
ventral: bottom of skull or front of body
lateral: toward the side
medial: toward the middle
ipsilateral: structures on the same side of the body
contralateral: structures on opposite sides of the body
What are the two types of cells of the nervous system?
- supporting cells/neurogli/glia
- nerve cell/neurons
What are all the types of glial cells?
CNS glia:
- astrocytes
- microglia
- ependymal cells
- oligodendrocytes
PNS glia:
- schwann cells
- satellite cells
What do astrocytes do?
provide chemical and nourishment to neurons, regulate chemical composition of fluid surrounding neurons
Where are astrocytes located?
Processes of astrocytes surround capillaries and neurons of CNS
What are the function of oligodendrocytes?
form the myelin that surrounds many axons in CNS, each cell forms segments of myelin for several adhacent axons
What do nerve cells do?
transmit messages
What is the structure of a nerve cell?
- cell body (soma): metabolic center with nucleus surrounded by cytoplasm
- fibers (processes):
electrical signals towards cell body = dendrites; can be hundreds of dendrites
electrical signals travel away from the cell body = axons; each neuron only has one axon
What is ganglia?
collection of cell bodies in PNS
What are each axon terminal separated by?
synpatic cleft
What is a nuclei?
cluster of neuron cell bodies in CNS
What is a tract?
bundle of nerve fibers running through CNS
What is a nerve?
bundle of nerve fibers running through PNS
What is white matter?
dense collections of myelinated fibres
What is grey matter?
mostly unmyelinated fibres and cell bodies
What do sensory neurons receive?
impulses from sensory receptors to CNS, cell bodies are outside of CNS
- skin
- muscles/tendons
What is the sensory neuron for muscles and tendons?
proprioceptor
What is the sensory neuron for skin?
cutaneous sense organs