BIOL 252 Lab on reflexes and reaction time
The spinal cord carries ______ information from the spinal ______ to the _________
It carries ______ information from the brain to the spinal nerves
It does/does not cause reflexes
Sensory; nerves; brain
Motor
Does
White/gray matter contains a lot of myelin
White/gray matter does not contain myelin
What color matter are where signals are sent?
What type of matter contains unmyelinated axons, synapses, glial cells, and astrocytes?
What color matter are where decesions and processing is done?
White
Gray
White
Gray
Gray
Is your spinal cord as long as your spine?
When does your spinal cord stop growing? Where does it end? What is at its very end?
Nerve in the PNS is to _____ in the CNS? What is the definition of a nerve?
A bunch of tracts in the CNS is called a _________
Ganglia in the PNS is to _________ in the CNS. What is the definition of a ganglia?
No
When you are 4 years old; L1/L2; nerve roots
Tract; a bundle of axons
Column
Ganglia; nucleus; a cluster of neurons
What is a cortex?
The cervical enlargement are where nerves that go to the ________ and ________
The lumbosacral enlargement are where nerves that go to the ______ and ______ attach
The conus medullaris is the ________ _______ of the cord
The cauda equina is the ________ ________ of nerve roots that come out of end of the spine
A cluster of gray matter on the brain's surface
Shoulders; arms
Pelvis; legs
Tapered end
Horse's tail
How many pairs of spinal roots exist? So, there are ____ in total. Each nerve has _____ roots
What does the ventral root contain?
What does the dorsal root contain? These roots are _____ .
What does SAD / MEV stand for?
What is the protective layer of the spine called?
31; 62; 2
Motor axons
Sensory axons; mixed
Sensory; afferent; dorsal / motor; efferent; ventral
Meninges [Hint: Men protect]
What does the meninges contain from superficial to deep?
What does the meninges do?
Dura matter; arachnoid matter; and pia matter [Hint: Dura Max; spider; pita)
Provide stability and shock absobtion
What is the very outermost layer of the meninges called? What does it contain? What is it for?
What is the second layer of the meninges called? What is it continuous with?
What is the third layer of the meninges called? What is it? What is an unofficial layer below it?
What is the fourth layer of the meninges do? What is it called?
The epidural space; blood vessels and adipose tissue To provide some cushion
Dura mater; epineurium
Arachnoid mater; a weblike network of elastic and collagen fibers; subarachnoid space
Contains CSF; pia mater
What do the ventral horns contain?
What do the lateral horns contain? Where are they only found?
What do dorsal horns contain?
What does the central canal contain?
Somatic motor nuclei
Autonomic nuclei; thoracic and upper lumbar
Somatic and autonomic sensory nuclei
CSF
What is a commissure?
What is the main white matter commissure?
Matter that crosses over from one side to another
The ventral white commissure
What is a column?
What direction do ascending tracts go? They are sensory/motor
What direction do descending tracts go? They are sensory/motor
A bunch of tracts that convey information to and from the brain
Upwards; sensory
Downwards; motor
Are all spinal nerves mixed with sensory and motor neurons?
How many pairs of spinal nerves exist?
What is an axon made up of (in terms of nerves)?
Yes
31
Axon = nerve fiber = fiber
How many spinal nerves are cervical?
How many spinal nerves are thoracic?
How many spinal nerves are lumbar?
How many spinal nerves are sacral?
How many spinal nerves are coccygeal?
8
12
5
5
1
We have an expert-written solution to this problem!
What is the first connective tissue layer in a nerve?
What is the second connective tissue layer in a nerve?
What is the third connective tissue later in a nerve?
Epineurium
Perineurium
Endoneurium
What does the perineurium wrap?
What does the endoneurium wrap?
Each fascicle, which are nerve fibers
Individual axons
Basically, what is a rami? Are they mixed?
Where does the posterior ramus go? Does it contain somatic and visceral? Does it contain sesory and motor?
A branch that comes out of the nerve; yes
To your back; yes; yes
Where does the anterior ramus do? It is the smallest/biggest branch; Does it contain somatic and visceral? Does it contain sesory and motor?
Carries information to and from all of your limbs; biggest; yes; yes
What does the rami communicantes carry? Where does it lead?
Carries all visceral information - like visceral motor and sensory; sympatheic ganglia
What carries visceral information?
Interoceptors
What is a dermatome? Are they absolute?
A specific region of skin that is innervated by a single pair of spinal nerves; no
What is a nerve plexus? How many major ones are in the body? What are they called?
Where is the cervicle plexuses?
Where is the brachial plexus?
Where is the lumabar plexus?
Where is the sacral plexus?
Where a bunch of nerves all meet together; 4; the cervical, brachial, lumbar, and sacral plexuses
C1- C5
C5-T1
T12 - L4
L4-S4
What are neuronal pools?
What is a neural circuit?
Functional groups of interconnected interneurons in the CNS
How these pools work together
What is a divergence circuit? What is it good for?
What is a covergence circuit?
What is a serial processing circuit?
What is a parallel processing circuit?
What is a reverberation circuit?
Where one source spreads information to multiple neurons; spreading info super fast
Where multiple sources spread information to one neuron
Where neurons and pools work in a sequence
A circuit in which neurons or pools process information at the same time
A positive feedback circuit loop
What is a reflex?
A reflex is either _________, where you're born with it, or _______, in which you learn to do it. Give an example of each.
Innate reflexes are either positive/negative feedback
A reflex is either _______, in which it uses your skeletal muscle or _________, in which it uses your smooth muscles and glands
A reflex that only has one synapse is called ______, where one that has more than one synapse is called __________
A rapid, unconscious response to a stimuli
Innate; acquired; the star reflex or a brake-light reflex
Negative
Somatic; visceral
Monosynaptic; polysynaptic
Can you influence reflexes?
What is the neural pattern of a reflex called?
Why are they good?
What is the classic example of a reflex? What kind of reflex catergory is it?
Yes
A reflex arc
They are quick and consistent
The patellar reflex, which contracts to prevent your quads from getting stretched; a stretch reflex
What is a simple example of a reflex arc?
1) The arrival of a stimuli to a receptor
2) The activation of sensory motors
3) Information processing at the CNS
4) Activates a motor neuron
5) Effector becomes activated
What is a example of the flexor reflex? It is also what kind of reflex? It is monosynaptic/polysynaptic
What is reciprocal inhibition?
Your hand on a hot stove; a withdrawl reflex; polysynaptic
When you set off one side of motor neurons, you relax the other side of motor neurons
What is the crossed extensor reflex?
When you withdrawl, but then push away from the other side; it uses both side of your body