Physio quiz bukas na agad! Flashcards
refers to processes—such a
summation and coordination— that produce
coherency and result in harmonious function.
Integration
refers to the selective
combination and processing of sensory,
endocrine, and central nervous system (CNS)
information in ways that promote the harmonious
functioning of the whole.
Whole-animal integration
is a cell that is specially adapted to
generate an electrical signal—most often in the form of a brief, self propagating impulse called an action potential—that travels from place to place in
the cell.
neuron
nucleus and
metabolic center of the
cell
Cell body
fibers that extend from the cell body (dendrites and axons)
Processes
relay sensory signals
to integrative centers of the CNS
Afferent Neuron
relay control signals
(instructions) from the CNS to target cells that are under nervous control, such as muscle cells or secretory cells
Efferent Neuron
Endocrine control has two essential features:
It is BLANK and BLANK
slow and broadcast.
such as neurons, muscle
fibers, and a few others can generate
electrical signals
Excitable cells
are one of the most important kinds of electrical signals underlying the integrative activity
of nervous systems
Action potentials
results from intense,
localized increases in permeabilities to
specific ions—increases that are both voltage- and time-dependent
action potential
Action potentials are propagated along the axons
of neurones via
local currents.
The ability to
store charge. The lower capacitance results
in a greater distance before the threshold is
no longer reached.
Membrane Capacitance
This depends on
the number of ion channels open. The lower
the number of channels open, the greater
membrane resistance is.
Membrane Resistance
Is a specialized site of contact of a
neuron with another neuron
Synapse
a presynaptic
signal—usually an action potential— affects a postsynaptic cell.
Synaptic transmission
Refers to the ability to change the
functional properties of synapses.
Synapse Transmission
electric currents from one cell flow directly into the next cell, changing its membrane potential
Electrical Synapse
is a specialized locus where protein channels bridge the gap between two
cells, directly connecting their cytoplasm.
Gap Junction
provide a low-resistance
path for current flow, electrically coupling
the cells that they join.
Gap junctions
have a discontinuity between the cells
because the 20- to 30-nm synaptic cleft of a chemical synapse is
a barrier to direct electrical communication
chemical synapses
Ways of How Neurotransmitter Works (2)
Ionotropic receptors
Metabotropic receptors
produce fast changes in membrane potential (depolarization or hyperpolarization) by directly
increasing permeability to ions
Ionotropic receptors
have relatively slow, long-lasting modulatory effects on synaptic processes; trigger a signaling cascade of second messengers in the postsynaptic cell
Metabotropic receptors
is an increase in the probability that a cell will
generate an impulse (an action potential), or if the cell is already generating impulses, excitation causes an increase
in the impulse frequency.
Excitation
by contrast, is a decrease in the probability of
impulse generation or a decrease in impulse frequency.
Inhibition
are chemical messengers that carry, boost, and balance signals between neurons (also known as nerve cells) and target cells throughout the body.
Neurotransmitters
like dopamine and
glutamate, typically act directly on neighboring cells.
Small-molecule transmitters
small molecules like insulin and oxytocin, work more subtly, modulating, or adjusting, how cells communicate at the synapse.
neuropeptides
Criteria Neurotransmitter (4)
Presence of the chemical within the cell
Stimulus-dependent release
Action on the postsynaptic cell
mechanism for removal
These types of neurotransmitters have excitatory effects on
the neuron, meaning they increase the likelihood that the neuron will fire an action potential.
Excitatory Neurotransmitters
(2) major excitatory neurotransmitters include
epinephrine and
norepinephrine
These types of neurotransmitters have inhibitory effects on
the neuron; they decrease the likelihood that the neuron will fire an action potential
Inhibitory Neurotransmitters
often referred to as neuromodulators, are capable of affecting a
larger number of neurons at the same time.
Modulatory Neurotransmitters
This naturally occurring amino acid acts as the body’s main inhibitory chemical messenger.
Gamma-aminobutyric acid
The most plentiful neurotransmitter found in the nervous system, and plays a role in cognitive functions such as memory and learning.
Glutamate
This powerful hormone acts as a neurotransmitter
in the brain.
Oxytocin
These neurotransmitters inhibit the
transmission of pain signals and promote feelings of
euphoria.
Endorphins
Also known as adrenaline, Blank is
considered both a hormone and a neurotransmitter.
Epinephrine
This naturally occurring chemical is a
neurotransmitter that plays an important role in alertness and is
involved in the body’s fight-or-flight response.
Norepinephrine
This organic compound acts as a neurotransmitter in the brain and spinal.
Histamine
Commonly known as the feel-good neurotransmitter,
dopamine is involved in reward, motivation, and additions.
Dopamine
A hormone and neurotransmitter, Blank plays an important role in regulating and modulating mood, sleep, anxiety,
sexuality, and appetite
Serotonin
are a type of
antidepressant medication commonly prescribed to treat depression,
anxiety, panic disorder, and panic attacks.
Selective serotonin reuptake inhibitors
This naturally occurring chemical acts as a
neuromodulator in the brain and is involved in suppressing arousing
and improving sleep.
Adenosine
Considered to be the energy
currency of life, ATP acts as a neurotransmitter in the central and
peripheral nervous systems.
Adenosine triphosphate
This compound plays a role in affecting smooth muscles,
relaxing them to allow blood vessels to dilate and increase blood flow
to certain areas of the body.
Nitric oxide
This colorless, odorless gas can have toxic and
potentially fatal effects when people are exposed to high levels of the
substance.
Carbon monoxide
This is the only neurotransmitter in its class.
Found in both the central and peripheral nervous systems, it
is the primary neurotransmitter associated with motor
neurons.
Acetylcholine
is a chemical substance produced and released by
nonneural endocrine cells or by neurons; it exerts regulatory influences on the function of other, distant cells reached via the blood;
and it is effective at very low concentrations
hormone
Hormones released by neurons are often referred to as
neurohormones
Secretory cells may be organized into discrete organs termed
endocrine glands
BLANK and BLANK are structured from chains of amino
acids
Peptide and protein hormones
are modified amino acids; synthesized
from tryptophan or tyrosine
Amine hormones
