Central Nervous System 1 Flashcards
What is the central organ of the nervous system?
Brain
What makes up the CNS?
Brain & spinal cord
What does the surface anatomy include?
- Cerebral hemispheres
- Cerebellum
- Brainstem
What is the average weight of a
- new born?
- adult human brain?
- 350-400g
- 1300-1400g
What are the functions of the CNS?
- Form a communication network
- Coordinates all the systems of body & allow to function
- Integrates the info that it receives
What do neurons receive messages from other neurons through?
dendrites
What are dendrites?
Carry message to neurons cell body
What do axons do?
Carry outgoing messages
What is a nerve?
A group of axons bundled together in the PNS
What is a nerve fascicle(fasciculus)?
Bundle of funicili
Funiculus (bundle of axons)
What is a tract?
A group of axons bundled together in CNS
What is a nucleus?
Collection of neural cell bodies in CNS
What is a ganglion?
Collection of neuron cell bodies in the PNS (except basal ganglia)
List the 2 functions of a myelin sheath
- Increases neuron efficiency
- Provides insulation
Name two demyelinating diseases
- Multiple sclerosis
- Guillain-Barre syndrome
What is white matter?
Bundle of axons each coated with a sheath of myelin
What is gray matter?
Masses of cell bodies and dendrites - each covered with synapses
List the 3 types of nerve tracts
- Association fibers
- Commissural fibers
- Projection fibers
List the 3 groups nerves are categorised by based on direction of the signals
- Afferent nerves (signals from sensory neurons to CNS)
- Efferent nerves ( CNS to target muscles & glands)
- Mixed nerves (both afferent & efferent axons)