Nervous System Test Flashcards
1
Q
What is a concentration gradient?
A
Difference between concentration of a substance in two compartments
2
Q
How do you calculate the concentration gradient?
A
ION(out) - ION(in)
3
Q
What is excitability?
A
The ability of a cell to send and receive electrical signals across the plasma membrane
4
Q
What does it mean to move down the concentration gradient?
A
From high to low concentration
5
Q
What does it mean to move up the concentration gradient?
A
From low to high concentration
6
Q
What is electrostatic repulsion?
A
When like charges repel
7
Q
What is equilibrium potential?
A
There is no net flux (no change in the ion concentration)
8
Q
What is an action potential?
A
A Rapid sequence of changes in the voltage across a membrane
9
Q
What are the steps of an action potential? (start to finish)
A
- Na+ gates open allowing Na+ to enter and depolarize the cell.
- The neuron reaches threshold and an action potential is propagated along the axon.
- The action potential peaks and Na+ gates close.
- K+ gates open and K+ exits the cell causing repolarization of the cell.
- K+ efflux and the Na+/K+ pump cause hyperpolarization of the cell.
- Natural leaky cells establish resting membrane potential.
10
Q
What are dendrites?
A
The site of signal input
11
Q
What is the soma?
A
Cell body
12
Q
What happens at the axon hillock?
A
Action potential is generated
13
Q
What is an axon?
A
The long string like part of the neuron that signals are sent down
14
Q
What is the axon terminal?
A
The site of signal output
15
Q
What is a synaptic cleft?
A
The gap between two cells filled with interstitial fluid
16
Q
What is a postsynaptic cell
A
The neuron located after the synapse that receives the signal
17
Q
What is a graded potential?
A
A change in the electrical potential on the membrane of an excitable cell
18
Q
What are the three channels present in the axon hillock?
A
K+ voltage gated channels
K+ leak channels
Na+ voltage gated channels
19
Q
What are the two types of circuits?
A
Converging and diverging
20
Q
Where does a converging circuit start?
A
A converging circuit starts in the PNS (sensory impulse)
21
Q
Where does diverging circuit start?
A
Starts in the CNS (motor impulse)
22
Q
What does a motor tract do?
A
Send signals from CNS to PNS
23
Q
What does a sensory tract do?
A
Send a signal from PNS to brain (located in CNS)
24
Q
What are the main two organs of the CNS?
A
The brain and spinal cord
25
What are 90% of the cells in the CNS?
Neuroglia
26
What are 10% of the cells in the CNS?
Neurons
27
What is the CNS supported by?
Cerebral spinal fluid (CSF)
28
What is an Axon?
Long thread like part of the neuron which impulses are sent from one cell body to another
29
What is the meninges?
A protective structure for the CNS
30
What are the three layers of the meninges? (superficial to deep)
- Dura mater
- Arachnoid mater
- Pia mater
31
What are the qualities of the Dura mater?
Thick, strong connective tissue layer
32
What are the qualities of the Arachnoid mater?
Thin, transparent fibrous membrane
33
What are the qualities of the Pia mater?
Delicate connective tissue layer
34
What are the functions of cerebrospinal fluid?
- Homeostatic regulation
- Support and cushioning
- Chemical and immunological buffering
35
What is the function of ventricles?
- Store CSF
- Provide a continuous flow of CSF between the brain and spinal cord
36
How does CSF move through the brain?
Ventricles
37
How is CSF produced?
Specialized tissues called choroid plexus and ependymal cells
38
What is the function of the blood brain barrier?
Tightly regulate the movement of ions, molecules, and cells between the blood and the brain
39
What type of cell is a neuron?
An excitable cell
40
What are graded potentials in dendrites called?
Synaptic potentials
41
What are the two types of synaptic potentials in dendrites?
EPSP and IPSP
- Excitatory
- Inhibitory
42
What is the function of neuroglia?
Regulate the internal environment of the CNS
43
What is the function of oligodendrocytes?
Create myelin sheath surrounding neurons in the CNS
44
What is the function of astrocytes?
- Neurotransmitter secretion/absorption
- Glycogenesis
- Fluid regulation
- Release of ATP
45
What is the function of ependymal cells?
Secrete CSF
46
What is the function of microglia?
- Remove damaged neurons
- Recognize infectious agents
- Prevent inflammation
47
What are the main function of the CNS?
- Process external sensory information
- Integrate information from a wide range of sources
- Send signals that control tissues in the body
- Consciousness perception of senses, memory, reason
48
What are three qualities of the spinal cord?
- Long thin tube
- Carry information to and from the brain
- Encased in vertebrae and meninges
49
What are dermatomes?
Locations where the body senses information
50
What are myotomes?
Muscle locations around the spinal cord
51
What are gyri?
Elevated ridges or hills
52
What are sulci?
Small grooves or valleys
53
What are fissures?
Deep grooves or canyons
54
What is the function of fibers?
Carry information within and between hemispheres
55
What is the function of association fibers?
Connect within one cortex
56
What is the function of commissural fibers?
Connect two cerebral hemispheres together
57
What is the function of projection fibers?
Connect cerebrum to other parts of the CNS and spinal cord
58
What is the medulla oblongata?
The relay station between the spinal cord and brain
59
What is the pons?
The relay station from medulla to higher cortical structures of the brain
60
What is the midbrain?
A nerve pathway of the cerebral hemisphere
61
What is the function of the cerebellum?
Controls BALANCE, eye movements, posture, learning complex movements, planning
62
What are the three parts of the diencephalon?
1) Thalamus
2) Epithalamus
3) Hypothalamus
63
What is the function of the thalamus?
Sensory relay center in our body
64
What is the function of the epithalamus?
Emotional and visceral responses
65
What is the function of the hypothalamus?
Regulation of homeostasis
66
What are the three parts of the cerebrum?
1) Cerebral cortex
2)Precentral gyrus
3) Postcentral gyrus
67
What is the function of the cerebral cortex?
Where complex processing information occurs
68
What is the function of the precentral gyrus?
Control of voluntary motor movement
69
What is the function of the postcentral gyrus?
Responsible for body awareness
70
What is the function of the hippocampus?
Learning and memory
71
What type of phase is sodium associated with?
The depolarization phase
72
What type of phase is potassium associated with?
The repolarization phase
73
What is the function of the frontal lobe?
Planning, motivation, and social judgement
74
What is the function of the cerebellum?
Balance and coordination
75
Do different areas of the brain communicate with each other?
Yes
- Difference areas of the brain DO communicate with each other
76
What are the three types of nerve fiber tracts?
1) Projection fibers
2) Commissural fibers
3) Association fibers
77
What is the function of commissural fibers?
Connect right and left hemispheres of the brain
78
What is the function of association fibers?
Connectv structures within the same hemisphere
79
What is the limbic system?
The emotional part of the brain
80
What is the function of the wernicke area?
Spoken and written language
81
What happens in the precentral gyrus?
Where motor somatosensory sense begin
82
What is the function of the vestibulospinal tracts?
Balance and posture
83
What is the function of reticulospinal tracts?
Locomotion and postural control
84
What is the function of rubrospinal tracts?
Primarily innervates muscles associated with flexion
85
What does innervate mean?
Supply with nerves
86
What are the three parts of a motor pathway?
1) Cerebral cortex
2) Spinal Cord
3) Skeletal muscles (or other effector organs)
87
Where do lower motor neurons originate?
The ventral horn
88
How do lower motor neurons correspond to different skeletal muscles?
They correspond ANATOMICALLY
89
What are the two types of motor neurons?
Alpha and gamma
90
What is the function of interneurons?
- Communication of neural impulses between neurons
- Allow for neural impulses to be relayed
91
What is the primary function of the motor cortex?
To generate signals to direct the movement of the body
92
What are the components of the motor cortex?
1) Primary motor cortex
2) Premotor cortex
3) Supplementary motor area
93
What is the function of the premotor cortex?
- Control muscle responses to visual or sound cues
- Stores motor memory
94
What is the function of the supplementary motor area?
Determine the amount of strength required for muscle movements
95
What is the function of the Primary motor cortex?
To generate signals to direct the movement of the body
96
What is the function of the upper motor neurons?
Carry the impulses for movement
97
What is the function of the cerebellum?
Adjust motor impulses to ensure muscle movements are precise and accurate
98
What is the function of muscle spindles?
Prevent overstretching or stretching too fast
99
What is the function of the golgi tendon organ?
The golgi tendon organ tells us how much tension the muscle is exerting
