Nervous System and Special Senses Flashcards
1
Q
What is the function of the Nervous system
A
To maintain homeostasis
2
Q
What does the body use to maintain homeostasis
A
Negative feedback
Using the end redial to to inhibit the cause
3
Q
What are the two main systems of the nervous system
A
Central nervous system
Peripher nervous system
4
Q
What are the two main things in a central nervous system
A
Brain and spinal cord
5
Q
What are the two nerves involved in peripher nervous system
A
Somatic nerves
Autonomic nerves
6
Q
What nerves are voluntary
A
Somatic nerves
- sensory
- motor
7
Q
What nerves are involuntary
A
Autonomic nerves
Involving sympathetic and parasympathetic
8
Q
Parasympathetic Nervous System
A
Restores the body after stress
9
Q
Sympathetic Nervous System
A
Prepares body for stress
Fight or flight
10
Q
What two main types of cells are in the Nervous System
A
Neurons
Glial Cells
11
Q
Neurons
A
The functional units of the Nervous System
12
Q
Glial cells
A
Non-conducting support cells of the Nervous System
13
Q
Bundle of Neurons
A
Single nerve fibres is known as a nerves
14
Q
Dendrites
A
Cytoplasmic projections that carry the nerves impulse to the cell body
Some neurons have specialized dendrites known as sensory receptors
15
Q
Cell Body
A
House the nucleus and the organelles of the neuron
The position of the cell body in a reflex arc will indicate the type of neuron
- main receptors
- signal doesn’t go to brain but spinal cord
16
Q
What type of neuron is the Spinal cord
A
Interneuron
17
Q
White matter vs grey matter
A
White matter has myelin sheath
18
Q
Axon
A
Cytoplasmic extension tat carries the nerves impulse away from the cell body
Most axons are almost entirely covered by Schwann cells
19
Q
Schwann cells
A
Glial cells that surround the axon and secrete the myelin (acts as inculcation)
Myelin is the cytoplasm of the Schwann cells which wrap around the axon
20
Q
What is a neurilemma
A
A thin layer surrounding the Schwann cell and axon which repairs damage to axon
21
Q
Nodes of Ranvier
A
Gaps in the myelin sheath where nerves impulse occur
Allow for saltatory conduction
-the process by which nerves impulse jump from node to node
22
Q
Axon Terminal
A
The point where a nerve impulse is passed to another neuron
Contains synaptic vesicles that contain neurotransmitter
23
Q
Neurons can be classified in what 3 categories
A
Sensory neurons
Interneurons
Motor neurons
24
Q
Sensory Neurons
A
Carries impulses received by sensory receptors to the CNS
25
Interneurons
Found in the CNS and pass signal to the brain or motor neurons
26
Motor Neurons
Carries impulse to effectors like muscles, organs, and glands
27
The reflex arc
A reflex is an involuntary and unconscious response to stimulus
A reflex arc is a simple nerves pathway that does not involve the brain
28
Where is the cell body of the sensory neurons (afferant neurons) located
Ganglion outside the spinal cord
29
Where is the interneuron located
Grey matter of the spinal cord
30
Where is the motor neuron (efferent neuron) located
Grey matter of the spinal cord and the axon extends out to the effector
31
What is the action potential also known as?
Nerve impulse
32
What is the action potential (nerve impulse)
The movement of an electrochemical charge along the length of the neurons
33
What is the electrochemical charge of the action potential due to?
The charge is due to the movement of ions (Na and K) across the neuron membrane
34
What is Ion Channels
The movement ions along a neuron is controlled by ion channels
35
What is ion channels function
They ensure Ions do not move down there concentration gradient at the wrong time
36
What are the two different ion channels
They are both sodium and potassium ion channels
37
What do I am channels depend on when opening and closing
They're opening and closing depends on membrane potential
How the inside charges compare to what is outside
38
What is resting potential in the action potential or nerve impulse
Sodium ions are found in a higher concentration outside of the neuron
Potassium ions are found in a higher concentration inside of the neuron
39
What charge does the membrane potential have in a resting potential , within the action potential or nerve impulse
The membrane potential is negative, The inside of the neuron is more negative compared to the outside
With the charge separation the membrane is said to be polarized
40
What is the depolarization in the action potential or nerve impulse
Stimulation of the neuron cause the sodium ion channels to open
Sodium travels down its concentration gradient into the neuron
41
What is the charge of depolarization in the action potential/nerve impulse
The influx/charge of sodium because the membrane potential to become positive
The influx must reach a threshold level to produce an action potential
42
Describe have the nerve impulse/action potential is propagated a long the neuron in depolarization
The influx of sodium ions will stimulate adjacent sodium ion channels to open propagating the impulse along the neuron
43
What is re-pull arise Asian in an action potential/nerve impulse
Sodium ion channels will close and the potassium ion channels will open
Potassium travels down the concentration gradient out of the neuron
44
What is the overall charge of repolarization and an action potential/nerve impulse
The efflux of potassium causes the membrane potential to become negative
The efflux is too strong that too much potassium leave
The Nora said to be hyperpolarized at this point
45
What is refractory period with an action potential/nerve impulse
The potassium ion channels close and the sodium/potassium pump restores resting membrane potential
It will transport three sodium ions out and to potassium ions in and use one ATP
46
Refractory period with an action potential/nerve impulse what is the membrane potential
The membrane potential approaches the resting membrane potential
Another action potential cannot occur until resting membrane potential
Turn around or hyperpolarized
47
Saltatory conduction
In the axon, ion channels are only found at the nodes of Ranvier
The nerve impulse is able to jump from node to node
48
How does my limited and unmyelinated axons compare in terms of their ability to transmit nerve impulses
Myelinated axons transmit nerve impulses faster than unmyelinated
49
Threshold levels
The minimum level of stimulus required for a neuron to fire
50
Can neurons have different threshold levels and if so how
Different neurons have different threshold levels. The more intense a stimulus, the more neurons with higher threshold that will fire.
Once the threshold level is reached, the neuron will fire completely
Higher intensity stimuli do not result in a bigger action potentials, The more intense as stimulus, the more frequent the neuron fires
51
What are the three ways the brain interprets a stimulus by
1. the number of neurons
2. The neurons respective threshold levels
3. The frequency of action potential's
52
Summation
When two or more neurons fire together on to another neuron with a higher threshold causing it to fire
53
Inhibition
When a neuron fires onto another and inhibits the subsequence neuron from firing
54
The synapse
The region between the axon terminal and another neuron's dendrites
It involves a presynaptic and a postsynaptic neuron
55
What is the space between a neuron and an effector also know as
Neuromuscular junction
56
What does Crossing the synapse involve
Transmission of the nerve impulse across the synapse involves neurotransmitters
Chemical messengers released by presynaptic neuron that bind to receptors on the postsynaptic neuron
57
What does the first step in synaptic transmission involve
The wave of depolarization reaches the presynaptic axon terminal
Calcium ions channels open in response resulting in reflux
58
What does the second step of synaptic transmission involve
Calcium ions fine to vessels containing neurotransmitters
What happens to the vessels following the vent
The stimulates the vessels to use with the axon terminal membrane
59
What is the third step of the synaptic transmission involve
The vesicles release the neurotransmitter into the synopsis (synaptic cleft)
The neurotransmitter following this event diffuse across the synapse and bind to receptors on the dendrites of the postsynaptic neuron
60
What is the fourth that of the synaptic transmission involved
Ion channels on the postsynaptic neuron open in response to the neurotransmitter
The postsynaptic neuron following this event will cause either deep polarization or hyperpolarization in the postsynaptic neuron
61
What is the fifth step in bowl in synaptic transmission involved
Enzymes in the synaptic cleft break down the neurotransmitter
Once the neurotransmitter is broken down the broken down neurotransmitter may be cycled by the presynaptic neuron
62
What is a neurotransmitter
The body has multiple neurotransmitters that cause either excitatory or inhibitory effects, or both
63
What is excitatory effects
Makes the post-synaptic neuron more permeable to sodium ions
64
What does inhibitory effect
Makes the postsynaptic neuron more permeable to potassium ions
65
Why is it essential for Neurotransmitters to have enzymes to break them down
Otherwise the neuron would remain in a constant state of depolarization
66
What is Acetylcholine
Results and muscle contractions
Acetylcholinesterase breaks down acetylcholine in the synapse
67
What gives drugs there various effects
The activation and suppression of inhibitory and excretory pathways is what gives drugs their various effects
Drugs are classified either stimulants or depressants based on their effects
68
Addiction theory
Neurons may respond to excess neurotransmitter by producing more receptorswhich will increase the threshold of the neuron to depolarization
69
What is the most consuming process of nerve impulse transmission
Diffusion of the neurotransmitter
The more synapse the slower signal
70
What is Acetylcholine primary function
Muscle control, memory formation, sensory responses
Excitatory
71
What is serotonin primary function
Initial movement control, mood regulation, appetite, sleep, muscle control
72
What is dopamine primary function
Reward pathways, Cognition, voluntary motion
73
What is norepinephrine primary function
Fight or flight response. increased heart rate, increase glucose and blood stream, increased oxygen in brain and muscles
74
What is the three layer protective membrane called in the CNS
Meninges
Dura matter
Arachnoid
Pia mater
75
What is the frontal lobe responsibility
Controls higher mental functions such as rational decision-making, right versus wrong, and socially acceptable behaviour
76
What is the parietal lobe responsibility
Involved with integrating sensory/Somatosensory information the significance of The parietal lobe different parts of the region control and response to specific body areas
77
What is occipital lobe responsible for
Involved in processing of visual information the pathway of the nerves from the eye through the brain is that the nerves I will lead to the lobe
78
What is the Temporal lobe responsible for
Involved in processing auditory information for significance responsibility of the low of the brain also is responsible for some short and long-term memory
79
What is the Cerebellum responsible for
Involved in coordinating muscle movement it is strongly involved in balance and body awareness
80
What is the cerebrum/cerebral cortex responsible for
Store sensory information, initiate voluntary action, involved in intellectual abilities
81
What is the corpus callosum responsible for
Connects the two hemispheres of the brain, also for communication between the 2 halfs of the brain
82
What is the Thalamus responsible for
Coordinate various sensory information from the cerebrum to the cerebellum
83
What is the hypothalamus responsible for
Largely in Baltimore containing homeostasis, Courtney's communication between the nervous system and the endocrine system
84
What is the olfactory bulb responsible for
Process information in regards to smell
85
What is the pituitary gland responsible for
I made your site of hormone production
86
What is the pons responsible for
Literally means bridge, maturely involved in relaying signal from the cerebrum to the cerebellum and Medela oblongata
87
What is the medulla oblongata responsible for
This side of autonomic nervous control some bodily activities that are controlled by the structure are the control of activities like breathing, heart contractions, digestive moment, and etc.
88
What is the midbrain responsible for
Largely a real life Centre for the berries I am here function also involved in the sleep wake cycle
89
What is sensory information
The sensory somatic system uses sensory neuron. This provides the CNS with information about external environment
90
What are the seven receptor types
The skin, proprioceptors, taste receptors, olfactory receptors, Photoreceptors, and Mechanoreceptors
91
Proprioceptors
Found in muscles, tendons, joints, and years. Response to limb and body movement
92
Taste receptors
Found in the tongue. Respond to taste
93
Olfactory receptors
Found in the nasal cavity. Respond to chemicals in the air
94
Photoreceptors
Found in the eye. Response to wavelengths of light
95
Mechanoreceptors
Found in the ear. Respond to wavelength of the sound
96
The human brain multiple inputs
The brain relies on multiple sensory information to make associations with objects the brain uses multiple inputs to make associations such as taste and smell receptors are closely linked to just terminate the taste of an object
97
Sensory adaptation
The process by which a sensory receptor become accustomed to a stimulus
