A&P Test 4
Card Set Information
A&P Test 4
Matireal for test 4 Biology 1140
Axons are classified into three groups according to the relationships among what three characteristics?
Diameter, Myelination, and Propagation Speed
What are the three Fibers of Axons?
A, B, & C Fibers
Are the largest myelinated axons with diameters ranging from 4 - 20 um; Carry action potentials at speeds of up to 120 meters per second, or 268mph.
Type A Fibers
Are Smaller myelinated axons, with deameters of 2 - 4 um;
Their propagation speeds average around 18 meters per second, or roughly 40 mph.
Type B Fibers
Unmyelinated axons with diamters less than 2 um; The action potentials are propagated at speeds of 1 meter per second, or 2mph.
Type C Fibers
The presynaptic and postsynaptic membranes are locked together at gap junctions in what type of synapse?
Integral membrane Protiens with pores that permit ions to pass between the cells.
In a chemical synapse the cells are not directly coupled. True or False?
Based on their effects on postsynaptic membranes, neurotransmitters are often classified into 2 categories. What are they?
The Effect of a Neurotransmitter on the postsynaptic membrane depends on the properties of the ______ not the ______ of the Neurotransmitter.
Receptor & Nature
What type of Neurotransmitter causes depolarization and promotes the generation of Action Potentials?
What type of Neurotransmitter causes hyperpolarization and supresses the generation of action potentials?
Synapses that release ACh are known as What?
4 areas where ACh is released are:
1. neuromuscular junctions involving Skeletal muscles
2. Many Synapses in the CNS
3. All neuron to neuron synapses in the PNS
4. All Neuromuscular and neuroglandular junctions in the parasympathetic division of the ANS
A Neurotransmitter that is widely distributed in the brain and portions of the ANS.
________, also called Noradrenaline, and synapses that release NE are known as ____ Synapses; Has an excitatory, depolarizing affect on the postsynaptic cell.
NorEpinephrine & Adrenergic
What CNS Neurotransmitter is released in many areas of the brain?
Neurotransmitter that has Inhibitory & Excitatory affects; Inhibitory effects play an important role in our precise control of movements.
A result of damaged or destroyed neurons that produce Dopamine could be ...
The use of Cocaine produces a "High" feeling that results from ....
Rises in dopamine concentrations at synapses near the brain.
A CNS Neurotransmitter that has a widespread effect on a person's attention and emotional states and may be responsible for depression.
Interactions among serotonin, norepinephrine, and other neurotransmitters are thought to be involved in the regulation of what?
Sleep & Wake Cycles
Neurotransmitter that generally has an Inhibitory Affect; once released, appears to reduce anxiety, and some antianxiety drugs work by enhancing this effect.
Gamma-aminobutyric, Or GABA
The Brain and Spinal Cord make up the ____; and the Cranial nerves and Spinal nerves constitute the _____.
CNS & PNS
The Spinal cord is surrounded by ___ Meninges and conveys ____ and ____ information.
The Adult spinal cord measures approximately ____ in length and has a maximum width of roughly ____.
expanded segments of the spinal cord dedicated to the sensory and motor control of the limbs.
Enlargements of the spinal cord
What Supplies nerves to the shoulder and upper limbs?
What provides innervation to structures of the pelvis and lower limbs?
The area of the spinal cord that becomes tapered and conical; inferior to the Lumbar Enlargement;
A slender strand of fibrous tissue that extends from the inferior tip of the Conus Medullaris
Every Spinal Segment is associated with a pair of ____ located near the spinal cord
Dorsal Root Ganglia
The entire spinal cord can be divided into ___ Segments on the basis of the origins of the Spinal Nerves
The Axons of the neurons form the _____ ____, which bring sensory information into tthe spinal cord.
A pair of ____ _____ contains the axons of motor neruons that extend into the periphery to control somatic and visceral effectors.
The Dorsal and Ventral Roots of each segment pass between the vertebral canal and and the periphery at the ____ _____.
Distal to each Dorsal Root Ganglion, the sensory and motor roots are bound together into a single ____ ____.
___ _____ Nerves are classified as ____ _____ Because they contain both Afferent, and Efferent Fibers.
Spinal Nerves & Mixed Nerves
What is the region of integration and commands initiation?
What Matter Carries information from place to place?
The ____ _____ Carries sensory information from the visceral organs.
The ____ ____ of each spinal nerve carries sensory information to the spinal cord.
The ____ _____ Forms just lateral to the invertebral foramen, where the dorsal and ventral roots unite.
The _____ _____ of each spinal nerve contains the axons of somatic motor and visceral motor neurons.
Functional groups of interconnected Neurons are called...
5 circuit pattens of interactions among neurons are:
3. Serial Processing
4. Parallel Processing
The spread of information from one neuron to SEVERAL Neurons.
Several neurons synapse onto a SINGLE Neuron.
Information is relayed in a stepwise fashion from one neuron to another or from one neuronal pool to the next.
Several neurons or neuronal pools process the same information simultaneously.
Collateral branches of axons somewhere along the circuit extend back toward the source of an impulse and further stimulate the presynaptic neurons.