Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Anatomy 337 > Spinal Cord and reflexes > Flashcards

Spinal Cord and reflexes Flashcards

1
Q

dorsal root ganglian

A

cell bodies of sensory cells are located here

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

dorsal root

A

contains the afferent axons of the dorsal root ganglia

-thicker than ventral roots

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

ventral root

A

this is anterior to the dorsal root

  • contains efferent axons of the somatic motor neurons
  • at some levels, they contain visceral motor neurons that control peripheral efferectors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

filium terminale

A

a thread that extends from L1 to the dorsum of the coccyx (connects the spinal cord to the first coccygeal vertebra)
- an extension of the pia mater

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

why does gray matter increase in the cervical and lumbar enlargement

A
  • these contain interneurons

- the sections of the spinal cord that are concerned with the sensory and motor innervation of the limbs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what do interneurons do at the two places of enlargement in the spinal cord?

A
  1. relay arriving sensory information

2. coordinate the activities of somatic motor neurons that control complex muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

white matter

A

contains myelinated and unmyelinated axons organized into tracts and columns

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

central canal

A

this contains cerebral spinal fluid and runs longitudinally through the spinal cord
-is surrounded by gray commissure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

gray commissure

A

this is the area around the central canal

-contains axons crossing from one side of the cord to the other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

ascending tract

A

carries sensory information toward the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

descending tract

A

carries motor commands into the spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is a tract

A

it is within a column of white matter and is made up of axons that share functional/structural characteristics
-axons are all uniform in diameter, myelination, and conduction speed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is important to remember about the cervical spinal nerves

A
  • there are 8 spinal nerves even through there are only 7 cervical vertebra
  • C1-C6 has there corresponding nerve superior to it
  • the C7 vertebra has a spinal nerve superior (C7) and inferior to it (C8), and then every vertebra after has there corresponding nerve inferior to the vertebra
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is significant about the spinal cord stopping growth at about age four.

A

There vertebral column continues to grow to support the adult skeleton so in order for the spinal nerves to exit the vertebra at the right vertebral foramen, they must continue to grow
- this results in the caudal equina

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

dorsal ramus

A

the dorsal branch of the spinal cord that merges into the spinal nerve before arriving at the dorsal root
-carries sensory information

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

ventral ramus

A

this is the ventral branch of the spinal cord

-carries motor information

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

spinal root

A

this is where the dorsal ramus and the ventral ramus merge and the information (sensory and motor) also mix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

vertebral foramen

A

this is where the spinal cord passes through the vertebra

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

intervertebral foramen

A

this is where the spinal nerves leave the vertebral column

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

coccyx

A

attachment site for the pelvic floor muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

superior articular process of sacrum

A

this articulates with L5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

ventral foramina of sacrum

A

this is where the ventral rami of sacral spinal nerves pass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

dorsal foramina of sacrum

A

this is where the dorsal rami of sacral spinal nerves pass

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

meninges

A

the three layers of connective tissue that surround the spinal cord and brain

25
Q

dura mater

A

touch, most superficial layer of the spinal cord

- made of dense irregular connective tissue

26
Q

arachnoid mater

A

this is the middle layer

-a network of fibers and collagen that helps protect the brain and spinal cord from sudden impact

27
Q

pia mater

A

this is the inner most layer and can not be seen by the human eye except at the ilium terminal and the denticulate ligament

28
Q

anterior spinal artery

A
  • this supples the anterior portion of the spinal cord
  • this is 2/3 of the cord
  • located at the antero median fissure
29
Q

posterior spinal artery

A

this is two arteries that supply the other 1/3 of the spinal cord
-these are located at the posterior lateral fissure

30
Q

decussate

A

this means cross

- often used to refer to the spinal cord pathways as they cross to the other side of the spinal cord

31
Q

what is important to remember about all pathways that is typically not displayed in diagrams

A

-every pathway is paired and they occur on both sides of the spinal cord but it would get very messy in diagrams to show both

32
Q

what are similarities among sensory pathways

A
  • all have cell bodies in the dorsal root
  • all go through the posterior horn
  • all have 2 or 3 neurons in their pathways
33
Q

what does it mean to be 1st, 2nd, or 3rd order neuron

A
  • a first order neuron is the first one in the pathway and typically delivers the sensations to the CNS by synapsing on a 2nd order neuron
  • a 2nd order neuron typically has a cell body in the spinal cord or brain stem
  • a 3rd order neuron typically is used when tracts end in the cerebral cortex and it is the 3rd order axon that carries information from the thalamus to the specific region of the cortex
34
Q

Spinocerebellar pathway

A
  • this is used for proprioceptive and muscle sensation
  • Receptors: in the muscles and are the golgi tendon organs
  • can be dorsal or ventral
35
Q

dorsal Spinocerebellar pathway

A

this is for individual muscles

36
Q

ventral spinocerebellar pathway

A

this is for the limb as whole and knowing where it is in space

37
Q

what is really rare about the spinocerebellar pathway

A

even if they decussate, they end up crossing back over because all the information is always processes ipsilaterally

38
Q

where are lateral horns located and what do they contain

A

these are located between the T1 and L2 segments and contain visceral motor neurons

39
Q

dorsal column medial lemniscus pathway

A
  • this is used for fine discriminative touch
  • decussates in the brain stem and synapses there
  • this would be used when you feel in your bag for a utensil and can differentiate between pens, highlighters etc. without looking
  • This enters through the dorsal root, ascends to the brainstem through the dorsal column, synapses and decussates
40
Q

anterolateral system

A
  • this is used to sense pain, temp and crude touch
  • synapses in the posterior horn of the spinal cord and decussinates and then travels to the brain stem
  • this goes through the white matter on the anterior side but near the arch of the anterior horn and into the lateral white matter hence the name
41
Q

corticospinal tract

A
  • this is a motor pathway
  • this brings voluntary information out to the skeletal muscles
  • this decussinates in the brain stem and then travels down through the lateral columns of the white mattered then synapses in the anterior horn spinal cord before going out to the skeletal muscle on the ipsilateral side it traveled down
42
Q

lesion

A

this is an injury that can result in damage to all or part of the spinal cord

43
Q

motor pathways

A

the anterior horn is where the cell bodies of the somatic motor neurons are and the axons leave through the ventral root

44
Q

upper motor neuron

A
  • it has a cell body in either the cerebral cortex or the brain stem
  • this is excitatory or inhibitory of the lower motor neuron
  • it can make the decision
45
Q

lower motor neuron

A
  • these have their cell bodies in either the anterior horn or the brainstem cranial nerve nucleus
  • these are always excitatory
  • if they are given a stimulus they have no choice they go
46
Q

subcorticospinal pathways

A

can excite or inhibit the Lower motor neurons to modulate spinal reflexes, muscle tone, posture etc.
- they generally modulate/regulate movement

47
Q

amyotrophic lateral Sclerosis (ALS)

A

this is a motor neuron disease
- the upper and lower motor neurons are both involved and it begins with a slow progression of weakness and atrophy (begins at hands and extremities and eventually affects the diaphragm and breathing, causing death)

48
Q

proprioceptors

A
  • these are sensory receptors that receive stimuli from within the body
  • especially one that responds to position and movement.
49
Q

where are proprioceptors in the body

A

-they are in the skeletal muscles (muscle spindles), in the tendons (golgi tendon organs), and the joints (free nerve endings

50
Q

what are the functions of proprioceptors

A
  • monitor the tension, pressure and movement at a joint
  • sends input on body movements to the CNS
  • senses where we are in space (the body, where arms are etc.)
51
Q

reflex arc

A

rapid autonomic involuntary reactions of muscles to a stimulus
-can be ipsilateral or contralateral

52
Q

monosynaptic reflex arch

A

this has direct communication between the sensory and the motor neuron

53
Q

polysynaptic reflex arch

A

this uses an interneuron to relay information from the sensory neuron to the motor neuron

54
Q

muscle spindle

A

this monitors length/strength of a muscle

-when a stimulus results in the stretching of a muscle, the muscle reflexively contracts

55
Q

patellar tendon reflex

A

-this is an example of a monosynaptic pathway that uses a muscle spindle because the muscle is stretched and it reflexively contracts as a response

56
Q

golgi tendon organs

A

these are nerve endings located within tendons near a muscle- tendon junction

  • they monitor tension and force
  • these are what prevent us from lifting things that are too heavy so that we dont allow muscles to contract too much
  • can be overcome in times of adreneline or stress
57
Q

Golgi tendon reflex

A
  • this is a polysynaptic reflex

- the interneuron inhibits the lower motor neuron, which inhibits the muscle from contracting

58
Q

polysynaptic withdrawal reflex

A
  • a painful stimulus is sensed and info is sent to the spinal cord
  • interneurons receive the information and stimulate the motor neurons to directed flexor muscles to contract
  • simultaneiously the extensor muscles are inhibited so the traumatized body part can be withdrawn
59
Q

why is a polysynaptic withdrawal reflex a contralateral reflex

A

because you also need to stabilize the other side of the body so that you don’t lose balance

Anatomy 337 (39 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions