MODULE 2B : NEUROHISTOLOGY Flashcards
To process and interpret sensory input and decide if action is needed
INTEGRATION
Fast acting control system which responds to internal and external change
NERVOUS SYSTEM
Response to integrated stimuli. The response activates muscles or glands
MOTOR OUTPUT
Nerve fibers that carry information to the central nervous system
SENSORY (AFFERENT) DIVISION
Nerve fibers that carry impulses away from the central nervous system
MOTOR (EFFERENT) DIVISION
Branch of efferent division which is involved in voluntary reponse
SOMATIC NERVOUS SYSTEM
Branch of efferent division which acts on involuntary responses
AUTONOMIC NERVOUS SYSTEM
Functional and structural unit of the nervous system
NERVE CELL
Also known as the soma. Trophic and genetic center of a neuron
CELL BODY
Characteristics of Cell body
NUCLEUS : spherical, large, pale, centrally located
(“Fish Eye” appearance)
CYTOPLASM : basophilic (Nissl’s granules)
Causes the basophilic staining of the cytoplasm if cell bodies of neurons due to the abundance of reticulum and ribosomes
NISSL’S GRANULES
Short cytoplasmic processes that are specialized in receiving stimuli
DENDRITES
Sites of synaptic contact in dendrites
GEMMULES
Also known as the axis cylinder
AXON
It is a long cytoplasmic process that is specialized in conduction of action potentials
AXON
True or False : Axons does not have Nissl’s Granules
TRUE
Part of the perikaryon that leads directly into the axonal process
AXON HILLOCK
Part of the myelinated axon between the apex of the axon hillock and the beginning of the myelin sheath
INITIAL SEGMENT
Main trunk of the axon, excluding the initial segment
AXON PROPER
Also known as terminal telodendroglia which makes a synaptic contact
TERMINAL ARBIRIZATION
Also known as the terminal boutonw. Forms part of a synapse, the pre-synaptic membrane
TERMINAL END BULB
Immediate covering of the axon
MYELIN SHEATH
Sheath of Schwann Cells
NEUROLEMMAL SHEATH
Sheath of Key and Retzius. Outermost covering
HENLE’S SHEATH
Component of neurolemmal sheath
SCHWANN CELLS
Type of neuron which begin in the embryo as bipolar cells which are later fused to form a single T-shaped process
PSEUDO-UNIPOLAR
Type of neurons which has a single process
UNIPOLAR
Type of neuron which has more than two process
MULTIPOLAR
Type of neuron which serves as a linkage between afferent and efferent neurons
ASSOCIATION NEURON
Type of Neuron which has a long axon and large soma
GOLGI TYPE I
Type of neuron which has a short axon and small soma
GOLGI TYPE II
Parasympathetic postganglionic neuron
CHOLINERGIC NEURON
Sympathetic postganglionic neuron
ADRENERGIC NEURON
Supporting cells of the nervous system
NEUROGLIA
Neuroglial cells of the CNS
ASTROCYTES
OLIGODENDROCYTES
EPENDYMAL CELLS
Neuroglial cells of the PNS
SCHWANN CELLS
SATELLITES CELLS
Important supportive cells of the CNS. They have abundant processes which make connections to other tissues
ASTROCYTES
Form and maintain the. Myelin sheath in the CNS
OLIGODENDROCYTES
Astrocytes found in the grey matter
PROTOPLASMIC ASTROCYTES
Astrocytes found in white matter
FIBROUS ASTROCYTES
Line the ventricles of the brain and the central canal of the spinal cord
EPENDYMAL CELLS
Also known as neurolemma
SCHWANN CELLS
Capable of secreting myelin sheath in the PNS
SCHWANN CELLS
Produce myelin sheath in jelly-roll like fashion
SCHWANN CELLS
Gaps in myelin sheath along the axon
NODES OF RANVIER
Specialized Schwann cells found in the dorsal root ganglia and the autonomic ganglia of the PNS
SATELLITE CELLS
Myelinated large axons with long internodes for rapid impulse conduction
GROUP A FIBERS
Myelinated intermediate sized axons with short internodes for moderate rate of impulse conductions
GROUP B FIBERS
Unmyelinated small axons for slow rate of impulse conduction
GROUP C FIBERS
Type of nerve fiber found in motor and some sensory fibers
GROUP A FIBERS
Type of nerve fiber found mainly in visceral sensory fibers
GROUP B FIBERS
Nerve fibers include autonomic and some sensory fibers
GROUP C FIBERS
Loose connective tissue surrounding the individual nerve fiber
ENDONEURIUM
Dense irregular connective tissue enclosing a bundle or fascicle of nerve fibers
PERINEURIUM
Dense irregular connective tissue surrounding a peripheral nerve
EPINEURIUM
Aggregation of nerve cell bodies outside the CNS
GANGLION
Two types of ganglia
CRANIO-SPINAL GANGLIA
AUTONOMIC GANGLIA
Found in dorsal roots of all spinal nerves and some cranial nerves
CRANIO-SPINAL GANGLIA
Characteristics of cranio-spinal ganglia
SENSORY
PSEUDO-UNIPOLAR
NO SYNAPSE
Consists of sympathetic and parasympathetic ganglia
AUTONOMIC GANGLIA
Characteristics of Autonomic ganglia
HAS SYNAPSES
VICEROMOTOR
MULTIPOLAR
Originates from T1 through L2
SYMPATHETIC DIVISION
Neurotransmitters : Epinephrine and Norepinephrine
SYMPATHETIC DIVISON
Originates from the brain stem and S1-S4
PARASYMPATHETIC DIVISION
Terminal ganglia are at the effector organs
PARASYMPATHETIC DIVISION
Portion of the terminal bouton membrane closest to the target cell
PRE-SYNAPTIC MEMBRANE
Fluid filled space that guide the neurotransmitter across the gap
SYNAPTIC CLEFTW
Portion of the plasma membrane of the next neuron or target cell
POST-SYNAPTIC MEMBRANE
A property of neurons which is the ability to respond to stimuli
IRRITABILITY
Property of neuron which is the ability to transmit an impulse
CONDUCTIVITY
TRUE or FALSE : the plasma membrane at rest is non-polarized
FALSE
True or False : impulse travel faster when fibers are non-myelinated
FALSE
Sequence of depolarization or impulse transmission travels along the axon away from the cell body
ORTHODROMIC SPREAD
Impulse travels toward the cell body
ANTIDROMIC SPREAD
depolarization of myelinated axons occur only at the nodes of ranvier
SALTATORY CONDUCTION
Cold, heat and pressure on a nerve fiber can block impulse condunction
BLOCK SIGNAL TRANSMISSION
