Nervous fucking system Flashcards
(100 cards)
1
Q
cause a signal to be generated and propagated
A
excitatory
2
Q
making signal generation and propagation less likely
A
inhibitory
3
Q
● Connected to receptors
● Signals may be perceived as a conscious sensation
● carries receptors to CNS
A
afferent/sensory neurons
4
Q
function to convert external and internal environmental stimuli into nerve signals
A
receptors
5
Q
Carry receptors AWAY from the brain to the peripheral nervous system to effectors, such as muscles or glands.
A
efferent/motor neurons
6
Q
neurons that lie entirely within the central nervous system.
A
interneurons
7
Q
anatomy of a nerve
A
- ganglia
- axons
- cell body
- myelin
8
Q
are discrete bundles of nerve-cell bodies located outside the central nervous system
A
ganglia
9
Q
are often bundled together in a wrapping of connective tissue to form a nerve.
A
axons
10
Q
- concentric rings enclosing vertebrate nerves
- is an insulating layer, or
a sheath that forms around nerves, including those in the brain and spinal cord - allows electrical impulses to transmit quickly
A
myelin
11
Q
what produces myelin?
A
special glial cells: Schwann cells in the peripheral nervous system, and oligodendrocytes in the central nervous system.
12
Q
provide support and protection to the neurons (nerve cells), maintain homeostasis, cleaning up debris, and forming myelin
A
neuroglial cells (glial cells)
13
Q
radiating, star-like shape; serve as nutrient and ion reservoirs for neurons; provide a scaffold during brain development, enabling migrating neurons to find their destinations from points of origin
A
astrocytes
14
Q
astrocytes and smaller _____ are essential for the regenerative
A
microglial cells
15
Q
The process that follows brain injury; participate in several diseases in NS such as:
A
- Parkinsonism
- multiple sclerosis
- brain tumor development
16
Q
- an electrochemical message of neurons
- alike in all neurons in all animals
*“All-or-none” phenomenon - nerve fibers vary their signal by changing the frequency of signal conduction
- the higher the frequency (or rate) of conduction, the greater the level of excitation
A
nerve signal or action potential
17
Q
- neuron is selectively permeable to K+
- The permeability to Na+ is nearly zero because Na+ channels are closed
- Potassium ions tend to diffuse outward
A
resting membrane potential
18
Q
The decayed resting membrane potential of the fiber is prevented by
A
sodium pump
19
Q
helps to restore the ion gradients of both Na+ and K+
A
sodium-potassium pump
20
Q
is a rapidly moving change in electrical membrane potential. Brief depolarization of the membrane of the nerve fiber.
A
action potential
21
Q
- open suddenly, permitting Na+ to diffuse into the axon from the outside and depolarize the membrane.
- Then, Na channels close, and the membrane regains its resting properties and becomes impermeable to Na and permeable to K.
A
voltage-gated Na+ channels
22
Q
- action potential leaps from node to node, bypassing the insulated portions of the fiber
- Faster than continuous conduction
A
saltatory conduction
23
Q
two kinds of synapses
A
- electrical synapses
- chemical synapses
24
Q
- a mechanical link between two neurons that allows for the conduction of electricity
- points at which ionic currents flow directly across a narrow gap junction from one neuron to another
A
electrical synapses
25
* Much complex than electrical impulses
* contain packets or vesicles of specialized chemicals called neurotransmitters
chemical synapses
26
Neurons bringing action potentials toward chemical synapses
presynaptic neurons
27
neurons carrying action potentials away
postsynaptic neurons
28
a narrow gap that separates membranes at a synapse, having a width of approximately 20 nm.
synaptic cleft
29
filled gap between presynaptic and postsynaptic membranes that prevents action potentials
interstitial fluid
30
terminal that sits on dendrites or the cell body of the next neuron
synaptic gap
31
one of the most common neurotransmitters (PNS) illustrates typical synaptic transmission.
acetylcholine
32
located inside synaptic knobs which contain molecules of acetylcholine.
synaptic vesicles
33
a crucial part of the decision-making equipment of the CNS, modulating the flow of information from one neuron to the next.
synapse
34
nervous system of hydras (cnidaria)
nerve net
35
- a nervous system flatworms represent a distinct increase in complexity than radiate animals.
- This is the simplest nervous system showing differentiation into a peripheral nervous system and a central nervous system which coordinates everything
bilateral NS
36
ganglia burgeoned into textured nervous centers of great complexity
* highly developed sense organs
* capable of learning
cephalopods
37
brain region associated with learning which is largest in social insects
- shown changes in these structures with age and experience
mushroom bodies
38
basic plan of the vertebrate NS which terminates anteriorly in a large mass or brain.
Hollow, dorsal nerve cord
39
a process, by far the most important trend in the evolution of vertebrate nervous systems which is the great elaboration of size, configuration, and functional capacity of the brain
encephalization
40
compose the CNS
brain and spinal cord
41
The spinal cord encloses a central spinal canal and is additionally wrapped in three layers of membranes called _____.
meninges
42
protective bath that passes between the two layers of meninges that protects from shock
cerebrospinal fluid
43
- resembling in shape the wings of a butterfly
- contains the cell bodies of motor neurons and interconnecting interneurons.
inner zone of gray matter
44
contains bundles of axons and dendrites linking different levels of the cord with each other and with the brain.
outer zone of white matter
45
* Refers to many neurons that work in group
* Contains at least two neurons
reflex arc
46
A more common reflex arc
includes interneurons between the
sensory and motor neurons.
multisynaptic arc
47
response to a stimulus acting over a reflex arc
reflex act
48
* Center of the nervous system in all vertebrate animals and most invertebrate animals
* British physiologist Sir Charles Sherrington called it “great ravelled knot”
brain
49
Three Principal Divisions of the brains of early vertebrates
1. Forebrain (prosencephalon) – smell
2. Midbrain (mesencephalon) – vision
3. Hindbrain (rhombencephalon) – hearing and balance
50
Looks like an extension of spinal cord
hindbrain
51
three parts of the hindbrain
medulla oblongata, cerebellum, pons
52
The most posterior division of the brain, is really a conical continuation of the spinal cord.
medulla oblangata
53
an area that controls numerous vital and largely subconscious activities such as heartbeat, respiration, vascular tone, gastric secretions, and swallowing.
brain stem
54
* contains a thick bundle of fibers that carry impulses from one side of the cerebellum to the other
* connects both medulla and cerebellum to other brain regions
pons
55
* dorsal to medulla, controls equilibrium, posture, and movement, locomotion, agility of limb movement, and balance
cerebellum
56
automatic device used to correct the performance of a mechanism by means of an error-sensing feedback.
servomechanism
57
home to sensory processing, endocrine structures, and higher reasoning
forebrain
58
two main divisions of forebrain
- diancephalon (thalamus and hypothalamus)
- telencephalon (cerebrum)
59
is a major relay station that analyzes and passes sensory information to higher brain centers
thalamus
60
have several “housekeeping” centers that regulate body functions concerned with homeostasis, centers for regulating reproductive function and sexual behavior, and emotional behaviors.
hypothalamus
61
* Largest part of the brain
* control muscle functions and also control speech, thought, emotions, reading, writing, and learning
cerebrum
62
(Cerebrum) The anterior portion of the forebrain with two divisions:
Paleocortex (limbic system) and Neocortex (cerebral cortex)
63
- a deep-lying area because many of its functions depend on olfaction.
- it mediates several species-specific behaviors that relate to fulfilling needs such as feeding and sex
paleocortex (limbic system)
64
"nose brain"
rhinencephalon
65
site of spatial learning and memory
hippocampus
66
makes up approximately half the volume of the human brain
* contains discrete motor and sensory areas
neocortex (cerebral cortex)
67
large “silent” regions concerned with integrative functions that are not directly connected to sense organs or muscles.
association areas
68
refers to parts of the nervous system outside the brain and spinal cord
peripheral nervous system (PNS)
69
has two functional divisions of peripheral nervous system
- sensory or afferent division
- motor or efferent division
70
Two components in efferent division
- somatic nervous system
- autonomic nervous system
71
a set of 12 paired nerves in the back of your brain.
cranial nerves
72
12 cranial nerves
- olfactory
- optic
- oculomotor
- trochlear
- trigeminal
- abducens
- facial
- vestibulocochlear
- glossopharynx
- vagus
- accessory
- hypoglossal
73
governs involuntary, internal functions of the body that do not ordinarily affect consciousness
autonomic nervous system
74
Autonomic nerves originate in the brain or spinal cord and fibers consist of two motor neurons:
preganglionic autonomic neurons and postganglionic neurons
75
Subdivisions of the autonomic nervous system
Parasympathetic and sympathetic nervous systems
76
a network of nerves that relaxes your body after periods of stress or danger. It also helps run life-sustaining processes, like digestion, during times when you feel safe and relaxed. The informal descriptions for this system include the rhymes “rest and digest” or “feed and breed.”
parasympathetic nervous system
77
a network of nerves that helps your body activate its “fight-or-flight” response. This system's activity increases when you're stressed, in danger or physically active.
sympathetic nervous system
78
* a network of vessels that clear waste from the central nervous system, mostly during sleep
* promote efficient elimination of soluble proteins and metabolites from the central nervous system
lymphatic nervous system
79
* specialized sensory receptors designed for detecting environmental status and change
* first level of environmental perception; they are channels for bringing information to the central nervous system
sense organs
80
are biological transducers; specific for one kind of stimulus
sense organs
81
first described by Johannes Müller in 1830s
Law of Specific Nerve Energies
82
receptors are usually classified based on their
locations
83
a receptor near the external surface, keep an animal informed about its external environment
exteroceptors
84
a receptor in the internal parts of the body, receive stimuli from internal organs
interceptors
85
a receptor in muscles, tendons, and joints, sensitive to changes in tension of muscles and providing an organism with a sense of body position
proprioceptors
86
oldest and most universal sense in
the animal kingdom
chemoreception
87
a chemoreceptor in unicellular forms, locate food and adequately oxygenated water, and to avoid harmful substances
contact chemical receptors
88
a chemoreceptor: orientation behavior; toward or away from a chemical source
Chemotaxis
89
sensory hairs in which insect chemoreceptors are located
sensilla
90
present on the mouthparts, legs, wing margins, and ovipositor in females. They have a single pore at the tip and recognize four classes of compounds: sugar (attractive), bitter (repelling), salts, and water
taste sensilla
91
are located on the head on two pairs of olfactory organs: the antennae and the maxillary palps. Pores on the cuticular walls of these sensilla allow odorant and pheromone molecules from the environment to contact the olfactory receptor neurons
olfactory sensilla
92
species-specific compounds produced by social insects and other animals, including mammals, that constitute a highly developed chemical language.
pheromones
93
additional olfactory organ in many terrestrial vertebrates which responds to pheromones
vomeronasal organ (VNO or Jacobson’s organ)
94
sensitive to quantitative forces such as touch, pressure, stretching, sound, vibration, and gravity—in short, they respond to motion
mechanoreceptors
95
found in receptors of invertebrates (esp. insects) that are sensitive to both touch and vibration
tactile hairs
96
a mechanoreceptor in vertebrates; concentrated in areas, especially important for exploring and interpreting the environment
Superficial touch receptors
97
register deep touch and pressure in mammalian skin
Pacinian corpuscles
98
- unspecialized nerve fiber endings that respond to a variety of stimuli signaling possible or real damage to tissues
* Also respond to mechanical movement of a tissue and temperature changes
pain receptors
99
Pain fibers respond to small peptides, such as substance Pand bradykinins, which are released by injured cells
slow pain
100
are a more direct response of the nerve endings to mechanical or thermal stimuli
fast pain
