lecture test 1 human anatomy: chapter 12

Which of the channels shown in the figure opens and closes randomly

A

Which of the labeled cells in the diagram is a neuroglial cell that forms and maintains the myelin sheath around CNS axons?

A

Which of these types of channels is involved in leaking sodium and potassium ions across the membrane in order to establish the resting potential of a cell?

A

In the diagram, where is a node of Ranvier?

B

Which of the diagrams in the figure represents a ligand-gated channel?

B

Which of the labeled cells in the diagram is a neuroglial cell that removes debris and acts as a phagocyte?

B

this part of the neuron contains the nucleus and Nissl bodies.

B

This type of neuron has one dendrite and one axon emerging from the cell body.

Bipolar neuron

Which part of the diagram is considered nerve fiber?

Both A and D

Chromatolysis refers to

Break up of Nissl bodies after neural injury.

Which diagram represents a reverberating circuit?

C

Which of the labeled cells in the figure is NOT a neuroglial cell?

C

Which type of circuit is used to lengthen the output signal in physiological processes like regulation of the breathing pattern?

C

Which type of circuit is involved in solving mathematical problems?

D

This type of neural circuit consists of a single presynaptic neuron synapsing with several postsynaptic neurons.

Diverging circuit

In the CNS, this structure is produced by oligodendrocytes.

E

This part of a neuron contains the nucleus and cytoplasm of the Schwann's cell that has formed a myelin sheath around the axon.

E

This structure electrically insulates the axon of a neuron to increase the speed of nerve impulse conduction.

E

In the process of spatial summation, _____ are added together and _____ are subtracted from that total to determine whether _____ will be created at the trigger zone of the postsynaptic neuron.

EPSPs; IPSPs; action potentials

Which of the labeled cells in the diagram is a neuroglial cell that produces and assists in the circulation of cerebrospinal fluid?

F

In the diagram, where are axon terminals?

H

Which of the following is NOT a type of channel used in production of electrical signals in neurons?

Ion-gated channel

Which of the following types of neurons is exclusively found in the cerebellum?

Purkinje cells

During this period, a second action potential can only be initiated by a larger than normal stimulus

Relative refractory period

Hearing your cell phone ring in an otherwise quiet lecture hall is an example of which of the following types of nervous system functions?

Sensory function

What specific type of unipolar neuron is shown in the diagram labeled B?

Type I cutaneous mechanoreceptor (Merkel disc)

Plasticity means

ability to change based on experience.

Which of the neurons is considered to be a bipolar neuron?

all of the neurons

Which of the following structures is labeled E in the diagram?

axon terminal

Which type of depression results in an individual with a manic-depressive illness.

bipolar disorder.

What is the structural classification of the neuron labeled B?

bipolar neuron

Which of the following types of neurons have one axon and one dendrite emerging from the cell body and are found in the retina of the eye, inner ear, and olfactory region of the brain?

bipolar neuron

During the resting state of a voltage-gated Na+ channel, 1. the inactivation gate is open. 2. the activation gate is closed. 3. the channel is permeable to Na+.

both 1 and 2 are true.

With respect to neurons, the term "nerve fiber" refers to

both axons and dendrites.

Which of the following structures is labeled C in the diagram?

cell body

The nervous system can distinguish between a light touch and a heavier touch by

changing the frequency of impulses sent to sensory centers.

The motor portion of the autonomic nervous system can be divided into

d) sympathetic and parasympathetic divisions.

Wallerian degeneration refers to

degeneration of the distal end of axon and myelin sheath after neural injury.

Which of the following structures is labeled A in the diagram?

dendrites

An excitatory neurotransmitter _____ the postsynaptic membrane.

depolarizes

Schwann's cells begin to form myelin sheaths around axons in the peripheral nervous system

during fetal development.

A postsynaptic neuron responds to neurotransmitters released by a presynaptic neuron by creating

either EPSPs or IPSPs

Faster communication and synchronization are two advantages of

electrical synapses

In temporal summation, a single presynaptic neuron stimulates the creation of action potentials in a postsynaptic neuron when it

fires at a fast enough rate that the sum of EPSPs in the postsynaptic neuron moves above threshold.

Which of the following neurotransmitters are used in virtually all of the inhibitory synapses found in the spinal cord?

gamma aminobutyric acid (GABA) and glycine

In an action potential, the current that flows down the axon of a neuron is generated by the movement of _____ across the membrane.

ions

Name the type of membrane channel that randomly opens and closes and is found in dendrites, cell bodies, and axons of all types of neurons.

leakage channel

Name the type of membrane channel that opens in response to chemical binding and is found in dendrites of some sensory receptors like pain receptors, and in the dendrites and cell bodies of interneurons and motor neurons.

ligand-gated channels

A depolarizing graded potential

makes the membrane less polarized.

Name the type of membrane channel that opens in response to touch, pressure, vibration, or tissue stretching and is found in the auditory receptors of the ear, and in touch and pressure receptors in the skin.

mechanically gated channels

Which of the following types of neurons is the most common type of neuron found in the brain and spinal cord?

multipolar neuron

Which of the following types of cells display the property of electrical excitability?

muscle cells and neurons

Which of the following types of electrical signals allow rapid long-distance communication within the nervous system?

nerve action potential

Saltatory conduction

occurs only in myelinated axons

Which of the following structures is labeled B in the diagram?

peripheral process

Diffusion, enzymatic degradation, and uptake by cells are all ways to

remove a neurotransmitter

Which of the following structures is labeled D in the diagram?

trigger zone

When a depolarizing graded potential makes the axon membrane depolarize to threshold,

voltage-gated Na+ channels open rapidly.

Name the type of membrane channel that opens in response to changes in membrane potential and is located in axons of all types of neurons.

voltage-gated channels