Notesale: Turn your study into money

Document Preview

Extracts from the notes are below, to see the PDF you'll receive please use the links above

---

Nervous Tissue:
Notes:
- Three functions: sensory, motor, integrative (analyzes sensory information)
- Peripheral: cranial nerves emerge from brain, spinal nerves form spinal cord; affert is
from sensory to brain and efferent is from brain to motor ie muscles and glands
...

 Myelin sheaths: protects, speed
- shwann cells in pns: wrap numerous times, neurlemma = outer nucleated
cytoplasmic layer; gaps are nodes of ranvier
...

- nerve fibre = neuronal process; nerve = bundle of nerve fibres that travel in same
path of PNS
...
Gray matter is
mainly cell bodies
 Nerve circuits:
-Diverging: single stimulates many
- Converging: Many stimulates one

- Reverberating: impulses from later cells stimulate eary cells in circuit (short term
memory)
- Parallel after discharge: single cell stimulates a group of cells that all stimulate a
common postsynaptic cell (math problems)
 Nervous system and repairs:
- plasticity maintained throughout life: sprouting new dendrites, synthesis of
proteins, changes in synaptic contance with other neurons
- Limited ability for regeneration: CNS = NO REPAIRS; PNS= repair damaged
dendrite or axons
...

- What are the two main divisions of the nervous system: The two main divisions
of the nervous system are the central and peripheral nervous system
...
The peripheral nervous system is
divided into the autonomic and somatic
...
In the synaptic junction
neurotransmitters are released from the synaptic vesicles at the presynaptic
terminal and are released to the dendrites of the post synaptic neuron
...

SPINAL CORD AND THE SPINAL NERVES:
 Spinal cord anatomy:
- Vertebral column: vertebrae, vertebral ligaments
- Three spinal meninges: a) dura mater is outter, extends from foramen magnum,
epidural space with fat and connective tissue surrounds it
...

- BETWEEN ARACHNOID AND PIAL LAYERS IS SUBARACHNOID
SPACE FILLED WITH CSF
...

 External anatomy:
- extends to level of second lumbar vertebra
- Two enlargements where nerves emerge to extremities: a) cervical enlargement
from fourth cervical to first thoracic
...

- Lower end is conus medullaris, extending from the caudal in lower lumbar and
sacral regions are spinal nerves called cauda equina
...

 Internal environment:
- core of gray matter (shaped like butterfly)
- surrounded by white matter
- gray matter consists of cell bodies ad neurons and white is myelinated axons
- gray matter is subdivided into regions called horns
a) anterior (ventral) gray horns (voluntary motion)
b) posterior (dorsal) gray horns is sensory
c) lateral gray horns (autonomic motor) only in thoracic, upper lumbar and sacral
segments of the spinal cord
...

- Reflex pathway includes: receptor, sensory neuron, integrating center, motor
neuron, effector
 Spinal Nerves: 31 pairs
- 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccygeal
- nerve is formed by merger of dorsal root and anterior root
...

- each spinal nerve supplies a specific segment of skin; area that provides sensory
input to dorsal root is dermatome
...

 Review questions:
- three different meninges and their function?: dura mater: outter most layer for
protection, middle is arachnoid, inner is pia: supplies nutrients and oxygen
- main features of the gross anatomy of the spinal cord: main features are
protection, attachment and nutrient
...

- Know the five basic components of a reflex arc
- How many spinal nerves are there? Group them into their different plexuses: 31
pairs of nerves: cervical plexuses, brachical plexuses, lumbar and sacral
...

- Cerebrum: Right and left cerebral hemispheres including the cerebral cortex
and basal ganglia
...
; central sulcus: separates frontal lobe from parietal; anterior to central is
precentral which is motor area; posterior gyrus is somatosensory area of cerebral
cortex
...

- limbic system: ring of structures on inner border of cerebrum and floor of the
diencephalon that encircle the brain stem; emotional aspects and memory for
survival; pleasure and pain
...

-Left hemisphere: Speech, writing and reasoning

---