Exam 12: Neural Tissue

The following are the main steps in the generation of an action potential. 1.Sodium channels are inactivated. 2)Voltage-gated potassium channels open and potassium moves out of the cell,initiating repolarization. 3)Sodium channels regain their normal properties. 4)A graded depolarization brings an area of an excitable membrane to threshold. 5)A temporary hyperpolarization occurs. 6)Sodium channel activation occurs. 7)Sodium ions enter the cell and depolarization occurs. The proper sequence of these events is

Ion channels that are always open are called ________ channels.

The basic functional unit of the nervous system are cells called ________.

When cholinergic receptors are stimulated,

Figure 12-2 The Nerve Action Potential Use Figure 12-2 to answer the following questions: -Which area of the graph shows when membrane potential approaches the potassium equilibrium potential?

If the potassium permeability of a resting neuron increases above the resting permeability,what effect will this have on the transmembrane potential?

A postsynaptic neuron will have an Excitatory Postsynaptic Potential (EPSP)when

The axon is connected to the soma at the

At the normal resting potential of a typical neuron,its sodium-potassium exchange pump transports

Active neurons need ATP to support which of the following?

Neuron cell bodies in the PNS are clustered together in masses called ________.

Figure 12-1 The Neuron Use Figure 12-1 to answer the following questions: -On which structure do most neuron to neuron communications occur?

A change in the conditions in the synaptic terminal can influence the soma as a result of ________ axoplasmic transport.

Which of the following interactions between electrical and chemical gradients does not lead to the establishment of a neuron's resting potential?

Rapid impulse conduction from "node" to "node" is called

In the peripheral nervous system,Schwann cells participate in the repair of damaged nerves by

The following are the steps involved in transmission at a cholinergic synapse. 1.Chemically-gated sodium channels on the postsynaptic membrane are activated. 2)Calcium ions enter the synaptic terminal. 3)Acetylcholinesterase hydrolyzes acetylcholine. 4)An action potential depolarizes the synaptic terminal at the presynaptic membrane. 5)The synaptic terminal reabsorbs choline. 6)Acetylcholine is released from storage vesicles by exocytosis. 7)Acetylcholine binds to receptors on the postsynaptic membrane. 8)Calcium ions are removed from the cytoplasm of the synaptic terminal. The correct sequence for these events is

Neurons that have several dendrites and a single axon are called

How would the absolute refractory period be affected if voltage-regulated sodium channels failed to inactivate?

The neurilemma of axons in the peripheral nervous system is formed by