Nervous System Flashcards
What are the primary functions of the nervous system?
Reaction to stimuli, control/integration of various activities of the body, government of movement
What two things does nervous tissue contain?
Neurons and Glial cells (neuroglia)
What is the structural unit of the nervous system?
Neurons
What are the components of a neuron?
Cell body, axons (myelin surrounding some), dendrites
What is the function of a neuron?
To transmit impulses by neurotransmitters
What is the function of a glial cell?
Supporting, Insulating, and nourishing the neurons
What are the four types of CNS Glial cells and two types of PNS Glial cells?
- Oligodendroglia 2. Astrocytes 3. Ependymal cells 4. microglia 1. satellite cells 2. Schwann cells (neurolemma)
What are the two components of the nervous system?
Central and Peripheral
What are the two structures that make up the central nervous system?
Brain and Spinal Cord
What are the two things that make up the peripheral nervous system?
Nerve fibers and cell bodies
Which of the nervous systems functions to integrate and coordinate outgoing signals?
CNS
Which of the nervous systems functions in higher mental thinking?
CNS
Which of the nervous systems functions to conduct impulses to the body?
PNS
What structure of the brain is an H shape?
Gray matter
What structure of the brain surrounds the gray matter?
White matter
What are the layers that support the SC, superficially to deepest?
Dura mater, Arachnoid mater, Pia mater
What are some neuropathies involving Schwann cells?
Charcot-Marie-Tooth, Guillian-Barre
What do Schwann cells function to do?
Support neurons
What type of nerve fibers are known as sensory?
Afferent
What type of nerve fibers are known as motor?
Efferent
How many pairs of spinal nerves are there?
31
Which nerve root is efferent in function?
Anterior (Ventral) Root
Which nerve root is afferent in function?
Posterior (Dorsal) Root
What forms at development that give rise to muscles, bones, and other connective tissue?
Somites
What type of somites are on the medial side?
Sclerotomes
What type of somites are on the lateral side?
Dermatomyotomes
What is known as the unilateral area of skin supplied by a single spinal nerve?
Dermatome
What is known as the unilateral mass of muscle supplied by a single spinal nerve?
Myotome
What does the posterior rami supply?
Nerve fibers to the synovial joints of the SC, epaxial muscles of the back, and the overlying skin.
What does the anterior rami supply?
Nerve fibers to the skin, hypaxial muscles of the ant/LAt trunk, upper and lower limbs
How many cranial nerves are there?
12 pairs
How many cervical nerves are there?
8 pairs
How many thoracic nerves are there?
12 pairs
How many lumbar nerves are there?
5 pairs
How many sacral nerves are there?
5 pairs
How many coccygeal nerves are there?
1 pair
What do somatic sensory fibers do?
Transmit sensations from the body to CNS
What do somatic motor fibers do?
Transmit impulses to skeletal muscle
What type of fibers transmit pain or subconscious reflex sensations from hollow organs to CNS?
Visceral Sensory Fibers
What type of fibers transmit impulses to smooth muscle and glandular tissues?
Visceral Motor Fibers
What are some variations to the NS?
Permanent disability, nerve degeneration, parathesia (pins-and-needles), Cutting nerve injury, ischemia
What is the function of the autonomic nervous system?
Stimulate Smooth muscle, cardiac muscle, and glandular cells
What is the function of the somatic nervous system?
Provide sensory and motor innervation
What are the two parts of the ANS?
Sympathetic and Parasympathetic
What neurotransmitter does the Sympathetic ANS typically liberate?
Norepinephrine
What neurotransmitters does the Parasympathetic ANS typically liberate?
Achetylcholine
The nerve cell body of what neuron is located in the gray matter?
Presynaptic neuron
What is the second neuron of the cell body?
Postsynaptic neuron
Where are the postsynaptic neurons located?
autonomic ganglia
What two locations contain nuclei of the SC?
Paravertebral ganglia and prevertebral ganglia
What is the main function of the sympathetic system?
Regulate BVs and facilitate emergency respones (fight or flight)
Where are the presynaptic parasympathetic nerve cell bodies located?
Cranial Parasympathetic outflow (in the gray matter)
In what two places can the presynaptic parasympathetic nerve cells exit the CNS?
Cranial nerves III, VII, IX, X OR sacral parasympathetic outflow via S2-S4
Primarily where are parasympathetic neurons located?
Viscera of head, neck and cavities of the trunk and erectile tissues of genitalia
What is the primary role of the parasympathetic nervous system?
Body conservation(sometimes Reverses the sympathetic nervous system)
What body part does the Enteric Nervous System usually intervene with?
GI tract
What information does the ENS provide?
The condition of the body’s internal environment
What do visceral reflexes regulate?
BP and chemistry
Visceral sensations at the conscious level can include what?
Pain, cramps, hunger, fullness, nausea
Which nerve is sensory innervated to the mid deltoid?
C5
C6 sensory innervates what area of the body?
Dorsal aspect of thumb web space
Which nerve is sensory innervated to the dorsal aspect of the middle finger?
C7
C8 sensory innervates what area of the body?
Medial border of 5th metatarsal
What nerve sensory innervates the medial forearm?
T1
What movement does the motor innervation of C1-2 control?
Cervical Flexion
What movement does the motor innervation of C3 control?
Cervical Side Bending
What movement does the motor innervation of C4 control?
Scapular elevation
What movement does the motor innervation of C5 control?
Shoulder ABD
What movement does the motor innervation of C6 control?
Elbow flexion
What movement does the motor innervation of c7 control?
Elbow extension
What movement does the motor innervation of C8 control?
Thumb ABD
What movement does the motor innervation of T1 control?
Finger ABD
What movement does the motor innervation of L1-2 control?
Hip Flexion
What movement does the motor innervation of L3-4 control?
Knee Ext
What movement does the motor innervation of L4-5 control?
Ankle Dorsiflexion
What movement does the motor innervation of L5 control?
Great toe Ext
What movement does the motor innervation of L5-S1 control?
Knee Flexion and ankle eversion
What movement does the motor innervation of S1-2 control?
Ankle plantar flexion
Which nerve is sensory innervated by the inguinal area?
L1
Which nerve is sensory innervated by the anterior mid-thigh?
L2
Which nerve is sensory innervated by the medial knee?
L3
Which nerve is sensory innervated by the medial malleolus?
L4
Which nerve is sensory innervated by the distal medial dorsum of foot?
L5
Which nerve is sensory innervated by the lateral border of the foot?
S1
Which nerve is sensory innervated by the Medial/posterior calcaneus?
S2