2025
|MOST COMMON QUESTIONS WITH CORRECTLY
VERIFIED ANSWERS|ALREADY A+
GRADED|GUARANTEED PASS
what is the study of the nervous system - neurology
Specialized cell of the nervous system - neuron
bundle of neuron with connective tissue and blood vessels - nerve
housed within skull, contains 100 billion neurons - brian
12 pairs emerge from the base of the brain - cranial nerves
connects to the brain throughout the foramen magnum and its surrounded by the vertebral
column - spinal cord
31 pairs emerge from the spinal cord - spinal nerves
small masses of nervous tissue located outside the brain/spinal cord - ganglia
network of neurons supplying the same area - plexus
monitor changes in internal/external environment - sensory receptors
detect internal/external stimuli
sensory (afferent) neurons carry this information to brain - sensory
process sensory information received - integrative
respond to stimuli
motor (efferent) neurons carry information from brain/spinal cord to effectors - Motor
what are the divisions of the nervous system - central nervous system and peripheral
nervous system
,consists of brain and spinal cord
source of thought,emotions, and memories - central nervous system (CNS)
consists of all nervous tissue outside of CNS : cranial nerves/branches, spinal nerves/branches,
ganglia and sensory receptors. and further divided into somatic,autonomic, and enteric -
Peripheral nervous system
under voluntary control
sensory neurons send message from head, body wall, and limbs to CNS - Somatic nervous
system
involuntary
sensory send message from abdomen/chest to CNS
Motor neurons send impulses to smooth and cardiac muscle
Has sympathetic and parasympathetic - Autonomic nervous system
Stimulates functions - sympathetic
inhibits functions - parasympathetic
Enteric Nervous System - "Brains" of the gut
Involuntary
controls digestive system
What are neurons responsible for? - sensing, thinking, remembering, controlling muscle
activity and regulating glandular secretions
support cell of the nervous system - neuroglia
Carries genetic information, maintains the neuron's structure, and provide energy to drive
activities - cell body
branches extensions that emerge from the cell body - dendrites
long,thin projection that joins the cell body at the axon hillock - axon
Encircles the axon ; produces myelin sheath - increases from birth to maturity ; increased the
speed of nerve impulse conduction - schwann cell
outer layer of Schwann Cell ; aids in regeneration on injured axons - neurolemma
,only in CNS
Myelinate parts of axons - Oligodendrocytes
what does the lack of neurilemma do - little regrowth after injury
gaps in myelin sheath - nodes of ranvier
junction between 2 neurons where communication occurs - synapse
transmitting neuron - presynaptic neuron
receiving neuron - postsynaptic neuron
how are synapses categorized - Axodendritic - from axon to dendrite
Axosomatic - from axon to cell body
Axoaxonic - from axon to axon
space between transmitting neuron and receiving neuron - synaptic cleft
Bulb - shaped swelling at the tip of some axons
Contain sacs called synaptic vesicle that store chemical neurotransmitters that influence that
activity of neurons, muscles, glands - synaptic end bulbs
chemicals that transmit action potential across synapse - neurotransmitters
promotes generation of action potential in receiving neuron - excitatory
prevents generation of action potential in receiving neuron - inhibatory
Inhibitory at neurons of the vagus nerve (slows heart rate) - acetylcholine
powerful excitatory effects - Glutamate/aspartate
Emotional response and some aspects of movement - Dopamine (excitatory/inhibitory)
Implicated in awakening from deep sleep, dreaming, regulation mood -
Norepinephrine/Epinephrine (excitatory)
inhibitory effects - Gamma Aminobutyric GABA/glycine
involved in sensory perception, control of mood and sleep induction - serotonin
Consists of bundles of mostly myelinated axons from many neurons
, Functions in nerve impulse propaganda; sensory impulses flow from body to brain, motor
impulses flow from brain to body - white matter
Consists of neuronal cell bodies, dendrites and axon terminals
Functions to receive and integrate incoming and outgoing information - gray matter
outermost layer of spinal meninges - dura mater
middle; spider-web appearance - aarachnoid
innermost; adheres to spinal cord - Pia mater
between arachnoid/pia mater ; contains cerebrospinal fluid - subarachnoid space
between dura mater/ arachnoid; contains interstitial fluid (between body cells) - subdural
space
seen where nerves from upper limbs arise - cervical enlargements
seen where nerves from lower limbs arise - lumar enlargements
inferior to lumbar enlargement ; conical portion - conus medullaris
anchors the spinal cord to coccyx - filum terminale
connect spinal nerve to a segment of the cord - root
contains sensory fibers that conduct impulses from PNS into CNS - posterior root
contains axons of motor neurons that conduct impulses from the CNS to effectors -
anterior root
covers individual axons - endoneurium
covers fascicles - perineurium
covers the entire nerve - epineurium
Supplies skin/muscles of head, neck, and superior part of the shoulders/chest - cervical
plexus
provides entire nerve supply of shoulders/upper limbs - brachial plexus
Supplies the anterolateral abdominal wall, external genitals, and part of the lower limbs -
lumbar plexus