Neurvous System 1 Flashcards
What is main role of nervous system?
Coordinates voluntary and involuntary actions and transmits signals to and from different parts of its body
What is role of CNS and components?
- acts as integrating center (sensory input comes in and info is inegrated and sent to outputs to tissues)
- Brain (80-100 billlion neurons)
- spinal cord (100 million neurons)
What is Peripheral nervous system?
- nervous tissue outside of brain and spinal cord
- sensory division (afferent)
- efferent division
What are branches of efferent division of PNS?
Autonomic (cardiac muscle smooth muscle, glands, some adipose tissue) which splits further into sympathetic and parasympathetic
Somatic motor neurons (skeletal muscle)
Subdivisions of afferent division?
Somatic sensory (skin, muscles, sensations)
Visceral sensory (internal organs)
Special sensory (taste, smell, sight, hearing)
What are neurons?
The basic signalling units of the nervous system
What are glia?
Support cells structurally and functionally
What is the cell body (soma)?
The control center, with processes that extend outward; dendrites and axons
- number and length of axons and dendrites depend on neuron
What are dendrites?
Receive incoming signals from neighbouring cells (input portion)
What are axons?
Carry outgoing signals from integrating center to target (output portion)
What are presynaptic terminals?
Contain transmitting elements, end of axon, communicate with other cells
What are functional categories of sensory neurons?
Pseudounipolar (1 axon that splits into 2: peripheral and central )
Bipolar (two equal axons: peripheral and central)
What are functional categories of interneurons?
Anaxonic (no apparent axon just dendrites)
Multipolar
a) multiple dendrites, one or more axon
b) five-7 dendrites each branching 4-6 times (classic multipolar)
What is functional category of efferent neurons?
Multipolar
What are interneurons?
Complex branching neurons that facilitate communication between neurons
