Section 3 - Organization of the nervous system Flashcards
What are the two branches of the nervous system?
Central (CNS) and peripheral (PNS)
What is included in the CNS? (2)
Encephalon (brain, brainstem, cerebellum) and spinal cord
What is included in the PNS? (1)
Peripheral nerves (sensory and motor)
Name the two branches of the autonomic nervous system
Sympathetic
Parasympathetic
Where does the autonomic nervous system signal originates from?
The brain stem and spinal cord
Define sympathetic
increases the activity of autonomic functions
Define parasympathetic
decreases the activity of autonomic functions
In some situations, there is a short cut
between sensation and motor action: the
signal does not need to reach the brain to
provoke a motor action. This process is
called a _____
reflex
Name the 3 majors levels of the CNS
- Cortical level
- Subcortical level
- Spinal cord level
What type of circuits does the spinal cord level contains? (4)
- Walking circuits
- Circuits for reflexes (controls movement)
- Circuits for body support
- Circuits for reflexes (control organ functions)
What are the 6 components of the subcortical level?
Brainstem, mesencephalon, hypothalamus, thalamus, cerebellum, basal ganglia
What is the main role of the subcortical level?
Controls subconscious body activities (arterial pressure, respiration, equilibrium, feeding reflexes, body temperature, wakefulness and sleep, hormonal regulation…)
T or F: cortical level is made of a superficial layer of white matter
False, a 2-4mm of grey matter
Name the functions that require the cortical level’s action (4)
- Information processing
- Memory storage
- Decision making
- Thought processes
The cerebral cortex is made of ____ matter
Grey
T or F: More than 99% of all sensory info is discarded by the brain as irrelevant and unimportant
TRUE
What is the role of the somatosensory system?
Transmission of somatic information from receptors to CNS
Where does the information transmitted from the somatosensory system go?
Along the spinal cord, reticular substance, cerebellum, thalamus to the cerebral cortex
Name the system based on the definition: Controlling body activities like skeletal muscle contraction, smooth muscle contraction and activity of exocrine and endocrine glands
Motor system for COORDINATION
What is the basic functional unit of the central nervous system?
Neuron
Name the 3 structures of the neuron
Cell body (soma)
Dendrites
Axon
Where is the signal processing in the neuron?
Cell body (soma)
In which structure does the signal input comes from?
Dendrites
Where does the signal output comes from?
Axon
Name the 4 types of neuron
- Unipolar
- Multipolar
- Pseudo-unipolar
- Bipolar
Which type of neuron has several dendrites & one axon and is the most common cell type?
Multipolar neuron
Which type of neuron has one main dendrite & one axon and is found in retina, inner ear & olfactory?
Bipolar neuron