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Nerve impulses travel more rapidly on myelinated axons because of saltatory conduction: action potentials leap between the nodes separating the glial cells that form the axon’s myelin sheath.

The varieties of membrane channels generate the transmembrane charge, mediate graded potentials, and trigger the action potential

In myasthenia gravis, a(n) autoimmune disease, the thymus gland produces antibodies to acetylcholine receptors on muscles, causing weakness and fatigue.

Amyotrophic lateral sclerosis (ALS) typically begins with problems with: weakness in the chest and throat. Sensory stimuli are to muscular responses as afferent is to efferent. Inez has myasthenia gravis. This means her body produces antibodies that reduce the effectiveness of: acetylcholine neurotransmitter

1. The nervous system has evolved a variety of synapses: o axodendritic between axon terminals and dendrites, o axosomatic between axon terminals and cell bodies, o axomuscular between axon terminals and muscles, o axoaxonic between axon terminals and other axons, o axosynaptic between axon terminals and other synapses. o axoextracellular A(n) synapse releases chemical transmitters into extracellular fluid, a axosecretory synapse releases transmitter into the bloodstream as hormones, and a dendrodendritic synapse connects dendrites to other dendrites. 2. Excitatory synapses are usually located on a(n) dendrites whereas inhibitory synapses are usually located on a(n) cell body(soma)

An ionotropic receptor’s pore or channel can be opened or closed to regulate the flowthrough of ions, directly effecting rapid and usually excitatory voltage changes on the cell membrane. Metabotropic receptors, which are generally inhibitory and slow acting, activate second messengers to indirectly produce changes in cell function and structure. Motor neurons in the brain and spinal cord send their axons to the body’s skeletal muscles, including the muscles of the eyes and face, trunk, limbs, fingers, and toes. Without these SNS neurons, movement would not be possible. Motor neurons are also called cholinergic neurons because acetylcholine is their main neurotransmitter. At a skeletal muscle, cholinergic neurons are excitatory, producing muscular contractions. Permanent responses to frequently occurring stimuli are biologically (or behaviorally and/or metabolically) efficient, but if stimuli change suddenly, a lack of flexibility becomes maladaptive.

Excitatory synapse :Brief depolarization of a neuron membrane in response to stimulation, making the neuron more likely to produce an action potential. Inhibitory: Brief hyperpolarization of a neuron membrane in response to stimulation, making the neuron less likely to produce an action potential. 1. Explain what happens during back propagation: Some neurons have voltage-activated channels on their dendrites that allow the reverse movement of an action potential into the neurons’ dendritic fields. learning—that is, how neural synapses adapt physically as a result of an organism’s experience.

Both have binding sites for the neurotransmitter. Both are embedded in the cell membrane of the postsynaptic cell. And you may have noticed some of the following differences between the receptor classes: 

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Ionotropic receptors have a membrane-spanning pore, while metabotropic receptors do not. Metabotropic receptors are attached to a G-protein complex, while ionotropic receptors are not Function diff:

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When the ionotropic receptor is activated, there are fast, direct effects on the postsynaptic cell.

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When the metabotropic receptor is activated, there are many possible effects on the postsynaptic cell, and the effects are slow, indirect, and potentially long-lasting

7 stages synaptic transmission: When the action potential enters the presynaptic terminal, the terminal becomes depolarized.

The depolarization opens voltage gated calcium (Ca2+) channels. The concentration of calcium ions is greater outside the presynaptic terminal than inside. The entry of Ca2+ causes the synaptic vesicles to fuse with the presynaptic terminal and release a chemical (neurotransmitter) into the synapse. The neurotransmitters bind to proteins called receptors on the postsynaptic terminal that can directly or indirectly open ion channels resulting in EPSPs or IPSPs. The binding of the neurotransmitter to the receptor leads to spreading of IPSPs or EPSPs through the neuron to the axon hillock where summation could occur to pass threshold. The neurotransmitter releases from the receptor and it is either metabolized (broken down) by enzymes or taken up into the presynaptic terminal via a transporter or taken up by transporters on astrocytes. Synaptic transmission can activate presynaptic autoreceptors resulting in a decrease of transmitter release.

Dr. Cicero places two electrodes a distance apart from each other on an axon, and when she passes an electrical impulse through the first electrode, the second electrode records an action potential because a ____nerve impulses_ has moved down the axon....