Nervous System Pt. II Flashcards
It provides a two-way conduction pathway to and from the brain.
Spinal cord
The spinal cord extends from the ___ to the ___.
Foramen magnum; first or second lumbar vertebra
It is a collection of spinal nerves at the inferior end.
Cauda equina
What part of the spinal cord houses interneurons?
Dorsal horns
They receive information from the sensory neurons in the dorsal root.
Dorsal horns
They house motor neurons of the somatic nervous system.
Ventral horns
They send information out the ventral root.
Ventral horns
What covers the spinal cord?
Meninges
Where do spinal nerves leave?
At the level of each vertebra
What root of the spinal cord contains axons?
Ventral root
It is associated with the dorsal root ganglia.
Dorsal root
In a nerve, what surrounds each individual fiber?
Endoneurium
Groups of fibers are bound into fascicles by what?
Perineurium
Fascicles are bound together by what?
Epineurium
How many pairs of cranial nerves are there?
12 pairs
What is the only pair to extend into the thoracic & abdominal cavities?
Vagus
What are the classifications of nerves in the PNS?
Sensory, Motor, Mixed (both motor and sensory)
Which of the 12 pairs of cranial nerves are sensory?
Olfactory, optic, and vestibulocochlear
What are the 12 cranial nerves?
Olfactory
Optic
Oculomotor
Trochlear
Trigeminal
Abducens
Facial
Vestibulocochlear
Glossopharyngeal
Vagus
Accessory
Hypoglossal
Which of the 12 cranial nerves are motor only?
Oculomotor, trochlear, abducens, accessory, hypoglossal
Which of the cranial nerves are both motor and sensory?
Trigeminal, facial, glossopharyngeal, vagus
True or False: There is a pair of spinal nerves at the level of each vertebra.
TRUE. It totals 31 pairs.
What forms the spinal nerves?
Combination of ventral and dorsal roots of the spinal cord
How are spinal nerves named?
The region from which they arise
It is a branch of a spinal nerve.
Ramus
A ramus contains what type of nerve fibers?
Both motor and sensory
What are the two types of rami?
Dorsal rami and ventral rami
These rami serve the skin & muscles of the posterior trunk.
Dorsal rami
These rami form a complex of networks for the anterior.
Ventral rami
Networks of nerves serving motor and sensory needs of the limbs.
Plexus
Plexuses form from the ventral rami of spinal nerves from what regions?
Cervical, lumbar, and sacral regions
What are the four plexuses?
Cervical, brachial, lumbar, sacral
The autonomic nervous system is also known as ___.
Involuntary nervous system
It regulates the activities of cardiac and smooth muscles and glands.
Autonomic nervous system
What are the two subdivisions of the autonomic nervous system?
Sympathetic and autonomic nervous system
What are the nerves in the somatic nervous system?
One-neuron system; originates in the CNS & axons extend to skeletal muscles
What is the effector organ of the somatic nervous system?
Skeletal system
What are the subdivisions of the somatic nervous system?
There are no subdivisions.
What is the neurotransmitter of the somatic nervous system?
Acetylcholine
The autonomic nervous system has a two-neuron system consisting of what neurons?
Preganglionic and postganglionic neurons
What are the effector organs of the autonomic nervous system?
Smooth muscle, cardiac muscle, glands
What are the neurotransmitters of the autonomic nervous system?
Acetylcholine, epinephrine, norepinephrine
Preganglionic neurons of the parasympathetic division originate from what regions?
Craniosacral regions
What comprises the craniosacral regions?
Cranial nerves III, VIII, IX, and X
S2-S4 regions of spinal cord
What is the site of preganglionic neuron origination?
Parasympathetic division
The parasympathetic division is also known as ___.
Craniosacral division
What are the effector organs of the parasympathetic division?
Terminal ganglia
What is the neurotransmitter of the parasympathetic division?
Acetylcholine
Preganglionic neurons of the parasympathetic division originate from what regions?
T1-L2
In the sympathetic division, where are the ganglia located?
Sympathetic trunk
True or False: Long preganglionic neurons and short postganglionic neurons transmit impulse from CNS to the effector.
FALSE. Short preganglionic neurons; long postganglionic neurons
What are the neurotransmitters of the sympathetic nervous system?
Norepinephrine and epinephrine
It is known as the “fight or flight” division.
Sympathetic division
It responds to unusual stimulus
Sympathetic division
The sympathetic division is known as the E division, what does it include?
Exercise
Excitement
Emergency
Embarrassment
This division is responsible for housekeeping activities.
Parasympathetic division
This division conserves energy and maintains daily necessary body functions.
Parasympathetic division
The parasympathetic division is known as the D division, what does it include?
Digestion
Defecation
Diuresis
When is the nervous system formed?
First month of embryonic development.
What does oxygen deprivation do to brain cells?
Destroys them
What is one of the last areas of the brain to develop?
Hypothalamus
What are some examples of congenital brain diseases?
Cerebral palsy
Anencephaly
Hydrocephalus
Spina bifida
Why do premature babies have trouble regulating body temperature?
Because the hypothalamus (in charge of regulating body temperature) is one of the last brain areas to mature.
What is indicated by the development of motor control?
Progressive myelination and maturation of child’s nervous system.
When does brain growth end?
Young adulthood
True or False: Neurons die throughout life and are not replaced.
TRUE. Thus, brain mass declines with age.
True or False: Neurons are amitotic.
TRUE. Neurons do not undergo cell division/mitosis.
True or False: Healthy aged people maintain nearly optimal intellectual function.
TRUE.
What is the major cause of declining mental function with age?
Disease, particularly cardiovascular disease
What are the characteristics of a reflex?
Rapid, predictable, involuntary response to a stimulus
Where do reflexes occur?
Neural pathways called reflex arcs
What are the two types of reflexes?
Somatic and autonomic reflexes
They are reflexes that stimulate the skeletal muscles.
Somatic reflexes
These reflexes regulate the activity of smooth muscles, heart and blood pressure, glands, and digestive system.
Autonomic reflexes
Pulling your hand away from a hot object is an example of what reflex?
Somatic reflexes
What are the five elements of a reflex?
Sensory receptor
Sensory neuron
Integration center (CNS)
Motor neuron
Effector organ
In a reflex, it reacts to a stimulus.
Sensory receptor
In a reflex, it carries messages to the integration center.
Sensory neuron
In a reflex, it processes information and directs motor output.
Integration center
In a reflex, it carries messages to an effector.
Motor neuron
In a reflex, it is the muscle or gland to be stimulated.
Effector organ
What are the two types of reflex arcs?
Two-neuron reflex arc and three-neuron reflex arc
It is the simplest type of reflex arc.
Two-neuron reflex arc
This reflex arc consists of five elements.
Three-neuron reflex arc
The patellar (knee-jerk) reflex is an example of what reflex arc?
Two-neuron reflex arc
The flexor (withdrawal) reflex is an example of what reflex arc?
Three-neuron reflex arc
What are the two functional properties of neurons?
Irritability and conductivity
It is the ability to respond to a stimulus and convert it to a nerve impulse.
Irritability
It is the ability to transmit the impulse to other neurons, muscles, or glands.
Conductivity
This muscle rolls the eye laterally.
Lateral rectus muscle
