A&P I- Chapter 12

Which of the following are considered types of effectors? - bone tissue -skeletal muscle -cardiac muscle -glands

-skeletal muscle -cardiac muscle -glands

The time when there is complete insensitivity of the plasma membrane to another stimulus.

Absolute Refractory Period

What catalyzes hydrolysis of ACh to remove it from the synaptic cleft.

Acetylcholinesterase

Which glial cell is starlike in shape and helps form the blood-brain barrier?

Astrocytes

Which glial cell acts as a phagocyte?

Microglial cells

_______ neurons are most common

Multipolar

Many dendrites and a single axon

Multipolar Neuron

EPSPs are caused by the movement of

Na+ into the cell

What type of cells produce the myelin sheath in the central nervous system (CNS)?

Oligodendrocytes

Includes cranial nerves, spinal nerves, and ganglia

PNS

Classify the given items with the appropriate group. More Abundant in Cytosol:

Phosphate Negatively charged proteins Potassium

Myelin sheaths mainly consist of which part of the glial cells that form them?

Plasma membranes

A time when there is a decrease in the sensitivity of the plasma membrane to further stimulation.

Refractory Period

The time when a stronger-than-threshold stimulus is needed to initiate another action potential.

Relative Refractory Period

What is the basic function of a neuron?

To transmit nerve impulses

A substance synthesized at the cell body must undergo _____ transport to reach the synaptic knobs.

anterograde

The _________ is the functional division of the nervous system that controls involuntary movement of smooth muscle.

autonomic motor nervous system

A difference in the number of charged particles between two sides of membrane forms a(n)

electrical gradient

The electrochemical gradient is formed from a combination of the ______ gradient and the _____ gradient

electrical; chemical

The glial cells that help produce and circulate CSF in the CNS are

ependymal cells

A cluster of neuron cell bodies found along a peripheral nerve is known as a(n)

ganglion

A(n) _______ is a cluster of neuron cell bodies with the PNS

ganglion

At an electrical synapse, presynaptic and postsynaptic membranes interface through

gap junctions

Negatively charged proteins and other large organic molecules are found in

greater amounts inside a neuron

The functions of astrocytes are to

help form the blood-brain barrier, assist neuronal development, and regulate the composition of the interstitial fluid

Which neurons are located only within the CNS?

interneurons

Neuronal pools are composed of

interneurons.

The component of nervous tissue that conducts electrical impulses is (are)

neurons

Neurolemmocytes produce myelin in the _____ nervous system.

peripheral

A graded potential that occurs in a postsynaptic neuron is known as a

postsynaptic potential

The opposition to the movement of electrical charge is known as

resistance

The relative difference in charge across the plasma membrane of a resting neuron is known as the

resting membrane potential

What type of neural circuit results in a repeating, cyclical response?

reverberating

As a result of a neurotransmitter opening up chemically gated sodium channels on the postsynaptic membrane,

sodium ions enter the cell.

A change in membrane potential insufficient to cause an action potential is known as a

subthreshold value

The junction between an axon and another cell is called a

synapse

A typical synapse in the CNS consists of a presynaptic neuron and a postsynaptic neuron, separated by a narrow space called the

synaptic cleft.

When threshold is reached, depolarization occurs with the same amplitude of potential change. This is known as

the all-or-none principle.

One dendrite and one axon

Bipolar Neuron

What neurons are: Special senses

Bipolar Neurons

Consists of the brain and spinal cord

CNS

Which terms are used for the structural classification of nerves?

Spinal & Cranial

Which segments of a neuron contain large numbers of voltage gated potassium channels and voltage gated sodium channels?

The initial segment and the conductive segment

Before a vesicle of neurotransmitter can be released which of the following must occur?

Voltage-gated calcium channel open and action potential reaches synaptic knob

A positive charge in the membrane potential is called

depolarization

The _____ functional division of the nervous system transmits info from the viscera to the CNS

visceral sensory division

An action potential is generated when threshold is reached, at which time

voltage-gated Na+ channels open

Categorize the following neurotransmitter/neuromodulator as to its effect on the postsynaptic neuron. Some neurotransmitters may belong to more than one category: INHIBITORY

Dopamine, Acetylcholine, GABA, Glycine

Categorize the following neurotransmitter/neuromodulator as to its effect on the postsynaptic neuron. Some neurotransmitters may belong to more than one category: EXCITATORY

Dopamine, Norepinephrine, Acetylcholine, Glutamate, Substance P, Nitric Oxide

Which ions have leak channels on the plasma membrane?

K+ and Na+

What neurons are: Most common type; innervate muscles and glands

Multipolar Neurons

____ are large cells that ensheath many different axons.

Oligodendrocytes

The cell body of a neuron does all of the following except: A. Release neurotransmitter into the synaptic cleft B. Produce synaptic vesicles containing neurotransmitter that are subsequently transported to the synaptic knob C. Conduct graded potentials to the axon hillock D. Receive graded potentials from dendrites

Release neurotransmitter into the synaptic cleft

What are the functional classes of neurons?

Sensory, Motor, and Interneurons

Classify the given items with the appropriate group. More Abundant in ISF

Sodium Chloride

One process with two branches; one extending to the CNS, one extending to the periphery

Unipolar Neuron

What neurons are: Most neurons in the PNS

Unipolar Neurons

The _______ is a period when a membrane cannot respond to another stimulus (no matter how strong).

absolute refractory period

A recently depolarized area of a cell membrane cannot generate an action potential because of the

absolute refractory period.

A flow of electrical current called a(n) _________ is generated within the initial segment of a neuron

action potential

The plasma membrane of an axon is called the

axolemma

Neurons that have only two processes attached to the cell body are called

bipolar

The nervous system is composed of:

brain, spinal cord, nerves, and ganglia

Ependymal cells help produce

cerebrospinal fluid.

The main activity of the _________ is propagation of an action potential along the axolemma

conductive segment

Which of the following is part of the PNS? a. microglia b. spinal cord c. brain d. neurolemmocyte

d. neurolemmocyte

A message traveling from one presynaptic neuron to multiple postsynaptic neurons is an example of a ____ circuit.

diverging

An axon with a large diameter transmits an impulse ____ than an axon with a smaller diameter.

faster

The components of the somatic sensory division are:

hearing, taste, joints, and muscles

Voltage is a measure of relative ______ energy

potential

Which type of Neuronal pool utilizes feedback to repeatedly stimulate the circuit?

reverberating circuit

An excitatory postsynaptic potential (EPSP) causes

the postsynaptic neuron's membrane potential to become more positive.