exam 1

(1,2,3.5)

What makes up the basic structure of a neuron?

cell body (soma), dendrites, an axon, and axon terminals

What does the soma contain?

nucleus and organelles supporting cell functions

Does the soma have a specific shape or does the shape vary?

the shape of the soma varies

Which part of a neuron's basic structure has a chemically excitable membrane and also receives input from other neurons and glia?

soma

What is the Greek word for body?

soma

What greek word means tree?

dendron

True or False: dendrites are only smooth.

False. Dendrites may be smooth or have spines

Which basic structure of a neuron is structurally similar to the somatic membrane?

dendrites

Which basic structure of a neuron conducts electrical potentials in a non-propagated, decremental fashion?

dendrites

What basic structure of a neuron has a membrane that is designed to conduct incoming info to the soma and is also chemically excitable?

dendrites

What is the greek word meaning axis?

axon

What basic structure conducts info (action potential) away from the soma?

axon

Why is the axon structurally different from soma and dendrites?

because the axon was designed to conduct action potentials w/o any change in magnitude

What is axonal transport?

moves proteins from soma to bouton and recycled materials back to soma

True or false: Dynein: anterograde transport

False. Dynein: retrograde transport and Kinesin: anterograde transport

What basic structure does not appear on all neurons and also has an electronically excitable membrane?

axon

Will there ever be more than one axon?

no IF there is an axon, there will only be one

What are axon branches called?

collaterals

What happens when an axon gets near its target?

it branches extensively- terminal branches (teledendria or terminal branches)

Where do terminal branches end?

in bouton or terminal endings

Where is the terminal bouton located?

at the end of a teledendron

What are bouton en passant?

varicosities along the length of the teledendron prior to terminal bouton

What do we use to categorize and name neurons?

shape, function, w/ or w/o myelin, and orientation & projections

What are the different shapes of the soma?

pyramidal cell, stellate cell, and granule cell

What conducts info to the CNS?

sensory (afferent)

What conducts info away from CNS?

motor (efferent)

What processes info between afferents and efferents?

interneurons (intermuncials)

What form circuits between close neurons?

local neurons

What interconnect local interneurons in different in different regions of the CNS?

relay neurons

What is the greek word meaning glue?

glia

What is another term for glia?

neuroglia

What are the 3 types of glia in the CNS?

astrocytes (astroglia), microglia, and oligodendrocytes (oligodendroglia)

What is the one type of glia in the PNS?

schwann cells (neurolemma)

What are astrocytes shaped like?

stars

What do astrocytes provide?

psychological support (nutrients/waste) and physical support

True of false: astrocytes isolate synapses and interact dynamically with neurons

true

Which type of glia forms scar tissue following an injury?

astrocytes

What type of glia are small cells that are derived from blood and are part of the immune system attacking microorganisms w/in the brain?

microglia

Which type of glia proliferate migrate to area of injury or where microorganisms are located w/in CNS?

microglia

What does phagocytic mean?

removes debri/waste

Which type of glia wraps around axons (not all axons, but most) and forms myelin?

oligodendria

True or false: myelin = segmented envelopment of axons

true

What are the small gaps between insulated segments of an axon called?

Nodes of Ranvier

Which type of glia has processes that extend to a series of nearby axons?

oligodendroglia

Which type of glia is only seen during the development of the CNS?

radial glia

Which type of glia ensheath all Peripheral Nervous System axons and sometimes gives rise to myelin?

schwann cells

True or false: each neurolemma cell extends a limited distance along associated axons

true

What type of glia is associated with myelin?

schwann cells

True or false: all schwann cells have myelinated axons?

false - not all axons are myelinated (a.k.a. nonmyelinated axons)

If the schwann cells' axon is myelinated what are between myelin cells?

Nodes of Ranvier

Which type of glia is a response to axon injury?

schwann cells

What is damaged in the CNS when microglia move in to clear damaged/dead tissue and astrocytes move in to form a glial scar blocking regeneration?

axons

What does it mean when myelin "disappears" temporarily, and schwann cells become phagocytic as well as actas guiding tubes for regenerating axons?

there was axon damage in the Peripheral NS

What is another way to describe reactive synaptogenesis?

axon sprouting

What is the process being described below?
When a nucleus is partially denervated, remaining inputs often will expand their synaptic surface area and sprouting additional bouton.

reactive synaptogenesis

What are the 2 parts that make up the Peripheral NS?

somatic NS and autonomic NS

What are the 2 parts that the somatic NS can be broken down into?

afferent (sensory) and efferent (motor)

What are the 2 parts that the autonomic NS can be broken down into?

sympathetic NS and parasympathetic NS

What are 2 parts that make up the CNS?

brain and spinal cord

What are the 3 basic subdivisions of the peripheral NS?

cranial nerves, spinal nerves, and autonomic NS

What is the term for a collection or bundle of axons found in the Peripheral NS?

nerve

What is the term for a collection or bundle of axons found in the CNS?

tract

What is the term for optic nerve or basal ganglia?

misnomer

What is the term for a collection of somas/dendrites in the Peripheral NS?

ganglion

What is the term for a collection of somas/dendrites in the CNS?

nucleus

How many cranial nerves are there?

12

What are cranial nerves?

nerves that connect directly to the brain

Name all 12 cranial nerves.

olfactory nerve, optic nerve, oculomotor nerve, trochlear nerve, trigeminal nerve, abducens nerve, facial nerve, auditory nerve, glossopharyngeal nerve, vagus nerve, spinal accessory nerve, and hypoglossal nerve

Which cranial nerves are afferent?

olfactory nerve, optic nerve, trigeminal nerve, facial nerve, auditory nerve, glossopharyngeal nerve, and vagus nerve

Which cranial nerves are efferent?

oculomotor nerve, trochlear nerve, trigeminal nerve, abducens nerve, facial nerve, glossopharyngeal nerve, vagus nerve, spinal accessory nerve, hypoglossal nerve

Which nerve runs from the retina of the eye to the optic chiasma where axons from both retinas co-mingle?

optic nerve

Which nerve innervates all but 2 muscles in the eye and also supplies involuntary parasympathetic intrinsic eye muscle (iris and ciliary body)?

oculomotor nerve

Which nerve controls eye movement?

trochlear nerve

Which nerve is the largest cranial nerve and supplies sensory info from the head?

trigeminal nerve

Which nerve receives sensory info from mouth, teeth, nasal cavity, cornea, dura mater, and anterior 2/3 of tongue (NOT TASTE)?

trigeminal nerve

What is tic doloroux

intractable facial pain

Which nerve affects eye movement?

abducens nerve

What is the sensory part of the facial nerve?

taste from anterior 2/3 of tongue

What is the motor part of the facial nerve?

muscles of facial expressions and some salivary and lacrimal glands

What are some other term for auditory nerve?

vestibulocochlear, stato-acoustic, and acoustic nerve

Which nerve attaches to the medulla?

glossopharyngeal nerve

What is the sensory part of the glossopharyngeal nerve?

taste from posterior 1/3 of tongue

Which nerve controls gag reflex?

glossopharyngeal nerve

What are some other terms for vagus nerve?

gypsy or wanderer

Which nerve arises from the medulla?

vagus nerve

Which nerve joins the vagus nerve innervating the thoracic and abdominal viscera?

spinal accessory nerve

Which nerve supplies striate muscles of larynx and pharynx, as well as supplies trapezius and sternocleidomastoid?

spinal accessory nerve

Which nerve arises from the medulla?

hypoglossal nerve

Which nerve supplies muscles of tongue and neck, and carries proprioceptive?

hypoglossal nerve

What are the following 4 points describing?
1. cranial nerves attach at irregular intervals
2. 2 cranial nerves aren't nerves, but projections of CNS (I and II)
3. cranial nerves lack dorsal and ventral roots creating variation in efferent and afferent components
4. some cranial nerves have more than one ganglion, some have none

the differences between cranial nerves and spinal nerves

What protects the spinal cord?

vertebrae

How many pairs of spinal nerves are there?

31

How are the 31 pairs of spinal nerves labeled?

by sequence and level where they enter/exit vertebral column

What are mixed nerves?

nerves that are both afferent and efferent

True or false: in the spinal cord, grey matter --> axons

false
grey matter--> somas/dendrites & white matter--> axons

How many spinal nerves are cervical (C1 is between skull and 1st cervical vertebrae)?

8

How many spinal nerves are thoracic?

12

How many spinal nerves are lumbar?

5

How many spinal nerves are sacral?

5

How many spinal nerves are coccygeal?

1