Neurophysiology Flashcards
What is the structures and function of the Central nervous system (CNS) ?
- Brain and spinal cord
2. Integrative and control centers
What is the structures and function of the Peripheral nervous system (PNS) ?
- Cranial nerves and spinal nerves
2. Communication lines between the CNS and the rest of the body
What is the structures and function of the Sensory (Afferent) division of the PNS ?
- Somatic and visceral sensory nerve fibers
2. Conducts impulses from receptors to the CNS
What is the structures and function of the Motor (Efferent) division of the PNS ?
- motor nerve fibers
2. Conducts impulses from the CNS to effectors (muscles and glands)
What is the structures and function of the Somatic nervous system ?
- Somatic motor ( voluntary)
2. Conducts impulses from the CNS to skeletal muscles
What is the structures and function of the Autonomic nervous system (ANS)?
- Viseral Motor ( Involuntary)
2. Conducts impulses from the CNS to cardiac muscles, smooth muscles, and glands
What is the function of the Sympathetic division of Autonomic nervous system (ANS)?
Mobilizes body systems during activity ( fight of flight)
What is the function of the Parasympathetic division of Autonomic nervous system (ANS)?
- Conserves energy
2. Promotes “housekeeping” functions during rest
The CNS is composed of ___ and ___ matter.
White and gray
The gray matter consist of ?
neuron bodies and dendrites
The white matter consists of ?
axon tracts
The adult brains weighs ____ kg, contains _______ neurons, and receives ___ % of blood flow.
1.5
100 Billion
20%
Describe the polarity of neurons in the sensory afferent nervous system.
Pseudounipolar
Describe the polarity of neurons in the sensory afferent nervous system
Multipolar
The immediate subdivion of the nervous system is ?
CNS and PNS
What is the functional unit of the nervous system?
neurons
What is the function of dendrites?
Receive impulses and conduct them to the neuron cell body.
What is the function of axon?
Conduct impulses away from the cell body to neuron ending
Nerve fiber vs peripheral nerve. General structure.
Nerve fiber: One axon and its surrounding cells and Connective tissue
Peripheral Nerve: a bundle of nerve fibers ( axons) with binding connective tissue and blood supply ( vasa nervorum)
CNS vs PNS. Groups of cell bodies are called ?
CNS: nuclei
PNS ganglia
What is a Schwann cell and where is it located.
A PNS glial cell that myelinates PNS axons.
What is the uninsulated gap between adjacent Schwann cells?
Node of Ranvier
What are the Glial cells in the CNS?
Oligodendrocytes
Microglia
Astrocytes
Ependymal cells
Each oligodendrocyte _____ ______ CNS axons
Myelinates several
What is the neural stem cell?
Ependymal
What cell is involved with NS maintenance?
Astrocytic glial cells
What is the most common glial cell?
Astrocytes
The 8 functions of astrocytes?
- Buffering K+ levels
- Recycling neurotransmitters
- Regulating adult neurogenesis
- Releasing transmitters that regulate neuronal activity
- Allows only certain compounds to enter brain
- formed capillary specializations in brain
- Gaps between adjacent cells are closed by tight junctions
- Role in angiogenesis
Describe sensory nervous system pathway from stimulus to spinal cord.
- Sensory receptors receive stimulus
- Information travels via Pseudounipolar sensory neuron towards CNS.
- Information travels through spinal sensory ganglion, into posterior sensory root, and finally reaches Dorsal horn of the spinal cord.
Describe sensory nervous system pathway from spinal cord to stimulus.
- Impulse starts at Ventral root.
- passes anterior motor root
- travels via somatic multipolar motor neuron to effector organ
Dorsal root vs Ventral root.
Type of fibers?
Dorsal has sensory
Ventral has motor
What is the function of Association/Interneurons?
integrate NS activity located entirely inside spinal cord
In the brain, the term ______ is used for small, locally projecting neurons in contrast to larger _______ neurons with long-distance connections.
interneuron
projection
The horns of the spinal cord are made of ____ matter.
Gray
How many spinal nerve pairs are there?
31
What is the three continuous sheets of connective tissue that covers the spinal cord and brain? ( General term )
Meninges
What are the three meninges from out to in?
Dura mater
Arachnoid
Pia matter
Which meninge contains the blood vessel?
Arachnoid
The region between the arachnoid and pia mater is filled with ?
Cerebrospinal fluid
Each spinal nerve has two nerve roots (except the first (motor only). What are they called?
- anterior or ventral root (motor)
* posterior or dorsal (sensory)
Each spinal nerve has a Rami That split into ?
Ventral (ant) Ramus and Dorsal (pos) Ramus
The ventral ramus supplies where?
body wall and limbs
The Dorsal ramus supplies where?
synovial joints of vertebrae, deep back muscles and skin
How many synapses occur outside the CNS through somatic and sensory pathways ?
None
How many neurons is involved with a automatic system impulse?
2
Where is the synapse located for the autonomic system ?
Outside the CNS in an autonomic ganglion
What are the effector organs of the autonomic nervous system?
Conduction system of cardiac muscle
glands
Smooth muscle