ch.12 A&P

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Which part of the nervous system controls smooth muscle, cardiac muscle, glands, and adipose tissue subconsciously?

The autonomic nervous system

The axon is connected to the soma at the synapse. synaptic knobs. collaterals. axon hillock. telodendria.

axon hillock.

Schwann cells are glial cells responsible for

producing the myelination around peripheral axons

The neurotransmitter glutamate opens channels that are permeable to sodium ions. What effect does glutamate produce on a postsynaptic neuron?

EPSPs

What type of neuroglial cell myelinates axons in the peripheral nervous system?

Schwann cells

Which functional class of neurons carries electrical signals that control the contractions of smooth muscle and cardiac muscle?

Visceral motor neurons

Poliomyelitis is caused by a virus that spreads easily in human populations. Most people with polio infections show no symptoms of disease. However, in a small percentage of victims, the virus enters the central nervous system and attacks the motor neurons of the spinal cord. Motor neurons are an example of what type or class of neuron?

a multipolar neuron that has two or more dendrites and a single axon

Both poliomyelitis and Guillain-Barré syndrome can involve paralysis where control over skeletal muscle function is lost. What is the neurotransmitter that a motor neuron uses to communicate with a skeletal muscle?

acetylcholine

Rachel decides to go swimming, but when she sticks her big toe into the water, she changes her mind because the water is too cold. The sensory neurons responsible for sending the message about the cold temperature of the water are

exteroceptors

Sensory (ascending) pathways distribute information

from peripheral receptors to processing centers in the brain

Collections of nerve cell bodies outside of the central nervous system are called: nuclei nerves ganglia tracts

ganglia

Voltage regulated channels can be found: at the motor end plate on the surface of the dendrites in the membrane that covers axons on the soma of neurons along the perikaryon of neurons

in the membrane that covers axons

Schwann cells in the PNS are functionally similar to _____ in the CNS. oligodendrocytes astrocytes ependymal cells microglia

oligodendrocytes

The period after an initial stimulus when a neuron is not sensitive to another stimulus is the: resting period repolarization period depolarization period refractory period

refractory period

Axons terminate in a series of fine extensions known as: telodendria synaptic knobs collaterals hillocks synapses

telodendria

A node along a myelinated axon represents an area where

there is an absence of myelin

Sensory neurons are responsible for carrying impulses

to the CNS

Compared to type A axons, type C axons are

unmyelinated slower propagating smaller diameter

The generation of an action potential in a neuron requires the presence what type of membrane channels?

voltage-gated channels

Which of the following is not a function of the neuroglia? secretion of cerebrospinal fluid maintenance of blood-brain barrier phagocytosis memory support

Memory

Which type of neuroglial cell functions in the central nervous system to engulf cellular debris, waste products, and pathogens?

Microglia

Which structural class of neurons consists of neurons with one axon and one dendrite?

Bipolar neurons

Rabies is a viral disease contracted from the bite of an infected animal. Rabies bypasses many immune system defenses by traveling in peripheral neurons to reach the CNS. Which method of transport is NOT used by the rabies virus to reach the CNS?

Anterograde flow

What part of the neuron is a long cytoplasmic process capable of propagating an action potential?

Axon

Which anatomical division of the nervous system consists of the brain and spinal cord?

Central nervous system

Which part of the nervous system performs the higher-order thinking required to complete a practice exam?

Central nervous system

What part of the neuron consists of the cytoplasm that surrounds the nucleus?

Perikaryon

Efferent pathways consist of axons that carry impulses

away from the CNS

Functions of astrocytes include all of the following, except forming a three-dimensional framework for the CNS. guiding neuron development. maintaining the blood-brain barrier. responding to neural tissue damage. conducting action potentials.

conducting action potentials

Myelin limits the movement of ions across the axon membrane, so the action potential "jumps" from node to node along the axon. This is an example of what type of propagation?

saltatory

Interneurons are responsible for

analyzing sensory inputs and coordinating motor outputs

EPSPs and IPSPs summate at the

axon hillock

An inhibitory postsynaptic potential (IPSP) is associated with: a change in sodium ion peremeability hyperpolarization opening of voltage-gated channels lowering the threshold for an action potential to occur

hyperpolarization

The sodium pump: pumps three sodium ions outside the cell and two potassium ions inside pumps two sodium ions outside the cell and three potassium ions inside pumps three sodium ions intside the cell and two potassium ions outside pumps two sodium ions intside the cell and three potassium ions outside

pumps three sodium ions outside the cell and two potassium ions inside

Glial cells that surround the neurons in ganglia are astrocytes. satellite cells. oligodendrocytes. ependymal cells. microglia.

satellite cells.

Saltatory conduction is made possible by: the myelin sheath large nerve fibers diphasic impulses rapid conduction of local potentials nissil bodies

the myelin sheath

What type of neuroglial cell participates in the production and circulation of cerebrospinal fluid?

Ependymal cells

The concentration of _______ is higher inside than outside the cell.

K+

The membrane is more permeable to

K+

The resting membrane potential is maintained by Na+-K+ pumps that actively transport _____ into and _____ out of the cell.

K+; Na+

Which of these ions is actively transported through the cell membrane to establish a resting potential? Cl Mg Ca K Na

Na

The concentration of ____ is higher outside than inside the cell.

Na+

Certain details about Mr. Roosevelt's case call into question whether he really suffered from polio. The pathological features that Mr. Roosevelt experienced were much more characteristic of Guillain-Barré syndrome, an autoimmune disease that involves the demyelination of peripheral nerves. Which neuroglia cells form the myelin sheath of motor nerves?

Schwann cells

Which functional division of the nervous system controls skeletal muscle contractions?

Somatic nervous system

A resting neuron is an unstimulated neuron that is not presently generating an action potential. The resting membrane potential is the separation of the relative positive and negative charges across the membrane of a cell at rest.

The separation of charges creates a voltage (electrical potential difference), which can be measured using a voltmeter. The resting membrane potential of a neuron averages -70mV (millivolts). All neural activities begin with a change in the resting membrane potential of a neuron.

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

4, 6, 7, 1, 2, 3, 5

Tyson decides to travel overseas, but he does not get all the needed vaccines before he goes on the trip. While on his trip, he contracts diphtheria. Which type of glial cells are particularly at risk from this disease?

Schwann cells

The cranial and spinal nerves make up what part of the nervous system?

The peripheral nervous system

The main functional difference between the autonomic nervous system and the somatic nervous system is that the activities of the ANS

are primarily involuntary, or under "automatic" control

The neuroglia cells that help supply neurons with nutrients are the

astrocytes

The part of a neuron that conducts impulses away from its cell body is called a(an): axon dendrite neurolemma soma nissil body

axon

The part of the neuron that performs the metabolic work of the cell to keep the neuron alive and functioning properly is the

cell body or soma

The portion of a neuron that primarily receives communication is the

dendrite

Opening of sodium channels in the membrane of a neuron results in: depolarization repolarization hyperpolarization increased negative charge inside the membrane reestabllishing the resting potential

depolarization

Ciliated CNS neuroglia that play an active role in moving the cerebrospinal fluid are: ependymal cells Schwann cells oligodendrocytes astrocytes satellite cells

ependymal cells

The most abundant class of neuron in the central nervous system is bipolar. pseudopolar. multipolar. anaxonic. unipolar.

multipolar

Saltatory propagation occurs in _________ axons, in which action potentials _________.

myelinated; move from one node of Ranvier to another

Adrenergic synapses release the neurotransmitter: acetylcholine norepinephrine dopamine serotonin GABA

norepinephrine

Which of the following are a type of glial cell found in the peripheral nervous system? astrocytes microglia ependymal cells satellite cells oligodendrocytes

satellite cells


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