1. The Nervous System- Nervous Tissue

2. The Nervous system has three major functions:
Sensory – _______________________________________________
Integration – interpretation of sensory information (information processing); complex (higher order) functions
__________– response to information processed through stimulation of effectors
______________
glandular secretion

3. General Organization of the nervous system
Two Anatomical Divisions
Central nervous system (CNS)
Brain
_____________
Peripheral nervous system (PNS)
All the neural tissue outside CNS
________________________
Efferent division (motor output)
Somatic nervous system
__________________

4. PNS (Peripheral Nervous System)
_____ (Central Nervous System)
PNS (Peripheral Nervous System)

5. General Organization of the nervous system
Brain & spinal cord

6. The CNS and PNS pass signals between each other
__________________________________________
PNS passes impulse to CNS
___________________
CNS passes impulse to PNS
_____________________

7. The PNS links the CNS to muscles and other organs
________________________________________________
The autonomic nervous system controls involuntary, functions
sympathetic nervous system: “__________”
parasympathetic nervous system: calms the body, conserves energy

8. Histology of neural tissue
Two types of neural cells in the nervous system:
_________ - For processing, transfer, and storage of information
Neuroglia – For support, regulation & protection of neurons

9. Neuroglia (glial cells)
CNS neuroglia:
astrocytes
_________________
microglia
_______________
PNS neuroglia:
Schwann cells (neurolemmocytes)
_________________

10. Astrocytes
create supportive framework for neurons
_____________________________________
monitor & regulate interstitial fluid surrounding neurons
secrete chemicals for embryological neuron formation
stimulate the formation of scar tissue secondary to CNS injury

11. Oligodendrocytes
_______________________________. Myelinated axons transmit impulses faster than unmyelinated axons
Microglia
___________________
phagocytize cellular wastes & pathogens

12. Ependymal cells
line ventricles of brain & central canal of spinal cord
______________________________(cerebrospinal fluid)

13. Schwann cells
surround all axons of neurons in the PNS creating a neurilemma around them. Neurilemma allows for potential regeneration of damaged axons
__________________________________________________
Satellite cells
support groups of cell bodies of neurons within ganglia of the PNS

14. Neuron structure

15. Most axons of the nervous system are surrounded by a _____________(myelinated axons)
The presence of myelin speeds up the transmission of action potentials along the axon
Myelin will get laid down in segments (internodes) along the axon, leaving unmyelinated gaps known as “nodes of Ranvier”
Regions of the nervous system containing groupings of myelinated axons make up the ____________
______________is mainly comprised of groups of neuron cell bodies, dendrites & synapses (connections between neurons)
of Ranvier

16. Classification of neurons
Structural classification based on number of processes coming off of the cell body:

17. Anaxonic neurons
______________________________________________________
functions unknown

18. Multipolar neuron
_________________________________________
most common type

19. ______________________cell body – one dendrite & one axon
Bipolar neuron
______________________cell body – one dendrite & one axon
only found in eye, ear & nose

20. __________________________________________
single process coming off cell body, giving rise to dendrites (at one end) & axon (making up rest of process)

21. Classification of neurons
Functional classification based on type of information & direction of information transmission:
_____________________–
transmit sensory information from receptors of PNS towards the CNS
__________________________________
transmit motor information from the CNS to effectors (muscles/glands/adipose tissue) in the periphery of the body
____________________
Association (interneurons) –
transmit information between neurons within the CNS; analyze inputs, coordinate outputs
are the most common type of neuron (20 billion)
__________________

23. Conduction across synapses
In order for neural control to occur, “information” must not only be conducted along nerve cells, but must also be transferred from one nerve cell to another across a ___________________
Most synapses within the nervous system are chemical synapses, & involve the release of a ________________________

24. The Structure of a Typical Synapse

25. Neuronal Pools