A & P Lecture Test 6

Type: Sensory

Function: Olfaction (smell)

Type: Sensory

Function: Vision (sight)

Type: Motor

Function: Moves eyeball & eyelid, focuses eye, pupil diameter (does sensation of eyeball proprioception)

Type: motor

Function: moves eyeball (& sense of eyeball proprioception)

Type: Mixed

Function:

Motor=muscles of mastication (chewing)

• 3 Sensory branches:
• 1.Ophthalmic-touch from scalp to nose
• 2.Maxillary-touch to nasal mucosa,
• upper palate
• 3.Mandibular-touch at anterior 2/3 of
• tongue, teeth, chin

Type: motor

Function: moves eyeball (&sense of eyeball proprioception)

Type: Mixed

Function:

• Motor=muscles of facial expression
• Sensory=tastbuds of anterior 2/3 of tongue

Type: Sensory

Function: hearing & equilibrium

Type: Mixed

Function:

• Motor=sallowing & saliation
• Sensory=taste of posterior 1/3 of tongue

Type: Mixed

Function:

• Motor=viscera of thoracic and abdominal cavities
• Sensory=proprioception of trunk

Type: Motor

Function: voluntary throat muscles for swallowing (proprioception)

Type: Motor

Function: moves tongue for speech (& sense of proprioception)

an enlarge area of the spinal cord to accommodate additional nerves to the upper limbs

an enlarge area of the spinal cord to accommodate additonal nerves to the lower limbs

nerves that exit the spinal cord at the sacrum

connective tissue tat holds th spinal cord to length

hole in the center of the spinal cord through which cerbral spinal fluid flows

contains somata of somatic & visceral sensory neurons (sensory nucleus)

contains viseral motor nuclei (lungs, heart)

contains somatic motor nuclei (skeletal)

contained unmyelinated axons that cross the spinal cord

contained myelinated axons that cross the spinal cord

contained myelinated axons that ascend/descend the spinal cord

(neurons that share common origins & distenations travel thru the same column)

contains axons of sensory neurons entering the spinal cord

contain somata of sensory neurons entering the spinal cord

contain axons of motor neurons exiting the spinal cord

31 pairs, all are mixed (sensory & motor)

covers the entire nerve

divides the nerve into bundles called fascicles

surrounds individual axons within the fascicles

all neurons carry sensory information from the skin, muscles, and viscera of the back enter the spinal nerve through the dorsal ramus.

all neurons carry sensory information from the skin, muscles, and viscera of the front, sides, and limbs enter the spinal nerve through the ventral ramus.

all neurons from viscera of the thoracic and abdominopelvic cavities pass through and autonomic nerve, then the white ramus of the rami communicates and then into the spial nerve, the dorsal root (with the soma in the dorsal root ganglion) and then into the visceral sensory nucleus.

all motor neurons carry somatic motor commands to the skin and muscles of the back leave the spinal nerve and exit through the dorsal ramus.

all motor neurons carrying somatic motor commands to the skin and muscles of the front, sides, and limbs leave teh spinal nerve and exit through the ventral ramus.

are made up of white (myelinated) and the gray (unmyelinated) rami they carry visceral sensory information from teh thoracic and abdominopelvic cavities into the spinal cord. they aslo can carry visceral (autonomic) motor information from the spinal cord to the viscera of the thoracic and abdominal cavities

motor commands leaving the spinal cord and innervating (communicate) viscera of the posterior body wall exit the visceral motor nucleus in the lateraly gray horn through a myelinated preganglionic fiber and pass out the ventral root and the spinal nerve.

motor commands leaving the spinal cord and innervating (communicate) viscera of the anterior and lateral body wall or the limbs exit the visceral motor nucleus in the lateral gray horn through a myelinated preganglionic fiber and pass out the ventral root and teh spinal nerve.

motor commands leaving the spinal cord and innervating (communicate) viscera of the thoracic cavity exit the visceral motor nucleus in the lateral gray horn through a myelinated preganglionic fiber and pass out the ventral root and the spinal nerve.

motor commands leaving the spinal cord and innervating (communicate) viscera of the abdominopelvic cavity exit the visceral motor nucleus in the lateral gray horn through a myelinated preganglionic fiber and pass out the ventral root and the spinal nerve.

is a network of interwoven nerves that innervate (communicate) a specific region of the body

Innervates (communicates) phrenic nerve which innervates the diaphragm.

Innervates (communicates) the radial nerve controls extensor muscles and the ulnar nerve innervates the flexor muscles of the forearm.

remember:

• E.R.-extension-radial nerve
• F.U.-flexor-ulnar nerve

the femoral nerve which innervates the skin of the inner thigh

the sciatic nerve innervates some of the thigh and the lower leg.

the pudendal nerve innervates the anal and urethral sphincters.

are automatic motor responses to specific stimuli that help maintain homeostasis and protect the body from physical damage

is the pathway of a neural reflex

stimulus/activation of sensory receptor: a receptor (intero- or exteroreceptor) detects a harmful stimulus

activation of sensory neuron: the receptor causes an action potential in the sensory neuron which then passes the information to the CNS through a sensory pathway

information processing: in the CNS the sensory neuron synapses on motor neurons and stimulates them to threshold

activation of motor neuron: an action potential in the motor neuron exits the ventral root towards an effector (muscle)

response at effector: the motor neuron stimulates an effector (skeletal or smooth muscle) and the appropriate feedback (motor response) is exhibited

inborn reflexes such as suckling, blinking, chewing

learned reflexes such as walking, balancing, riding a bike

reflexes involving cranial nerves like auditory and visual reflexes

reflexes involving spinal nerves like withdrawal reflexes

reflexes involving skeletal muscles that move the body

reflexes involving smooth or cardiac muscle (autonomic functions)

means to incorporate into a larger unit

ex. the brain has to take millions of fragments of info, visual, auditory, tactile, and others, and assemble or integrate that information into a large picture.

any change in the environment

arriving information

conscious awareness of a sensation

first order neurons are usually bipolar neurons and extend their axon through the dorsal root and the soma in the dorsal root ganglion. they then synapse on the second order neuron in the appropriate sensory nucleus in the posterior gray horn

the second order neuron has its soma in the posterior gray horn and extends its axon up the spinal cord through an ascending tract, usually crossing over at some point, and synapsing on the third order neuron in the thalamus.

the third order neuron has its soma in the thalamus and extends its axon through the cerebral nuclei and synapses on the cerebral cortex, usually in the primary sensory cortex

are all sensory tracts coursing through the spinal cord must go up or ascend the spinal cord toward the brain

Soma Location: in the dorsal root ganglion

Axon Location: through the dorsal root

Soma Location: the posterior gray horn

Axon Location: up the spinal cord through an ascending tract

Soma Location: the thalamus

Axon Location: the cerebral nuclei

has its soma in the brain (cerebrum or cerebellum) (usually the primary motor cortex) and extends an axon down the brain stem for cranial nerves, or down the spinal cord to the anterior gray horn for spinal nerves.

has it soma in the anterior gray horn (or medulla for crainal nervs) and extends its axon out the spinal nerve to the appropriate effector (muscle).

ascending tracts beging with the word spino-

descending or motor tracts usually end in the word -spinal.

extend from various levels of the spinal cord and carry sensations of pain, temperature, and crude touch to the thalamus.

extend from the spinal cord and carry sensations for proprioception to the cerebellum

extend from the primary motor cortex through the brain stem and to the somatic motor nuclei of the anterior gray horns

extend from the primary motor cortex out the cranial nerves that control movement of the eye, mandible, face, and some muscles of the neck and pharynx

extend from the medulla to the anterior gray horns and regulate involuntary control of balance and muscle tone.

extend from the midbrain (tectum) and extends out specific cranial nerves for eye movement, as well as the anterior gray horns for head, neck and arm movement for visual an dauditory reflexes

carries sensory input to the CNS through the afferent division.

are carried away from the CNS to the effectors (muscles) by the efferent division of the PNS

into the somatic and autonomic divisions

is entirely motor and controls conscious voluntary (skeletal) muscle movement.

somatic motor neurons extend from the anterior gray horns to the skeletal muscle without synapsing on the way.

is entirely motor and controls subconscious visceral effectors (smooth muscle of the visceral organs like digestive and urinary systems, and cardiac muscle of the heart)

Autonomic motor neurons extend from the lateral gray horns through the preganglionic fiber to an autonomic ganglion. at the autonomic ganglion they then synapse on another motor neuron (ganglionic neuron) that extends its postganglionic fiber from the ganglion to the effector (smooth or cardiac muscle)

sympathetic (thoracolumbar) and parasympathetic (craniosacral)