Anatomy and Physiology Chapter 7

Subdivision of the motor division responsible for controlling involuntary events

Autonomic Nervous System (ANS)

Brain and Spinal Cord

Central Nervous System

Integrating and Command Centers

Central Nervous System

Structural nervous system subdivision that consists of the brain and spinal cord

Central Nervous System (CNS)

Which of the stimuli in this experiment would be considered a threshold stimulus?

Stimulus 2

What cells of the nervous system are responsible for anchoring neurons to their blood vessels and controlling the extracellular fluid concentrations of potassium and neurotransmitters?

astrocytes

What is the most abundant glial cell in the central nervous system (CNS)?

astrocytes

The Schwann cell forms a myelin sheath around the ________.

axon

The part of the neuron that typically conducts nerve impulses away from the cell body is the ________.

axon

The term central nervous system refers to the ________.

brain and spinal cord

Which ion causes neurotransmitter vesicles to fuse with the axon's membrane during the conduction of a nerve impulse from one neuron to the next?

calcium

Ganglia are collections of ________.

cell bodies

The nervous system is structurally subdivided into two systems: ________ nervous system and ________ nervous system.

central, peripheral

The major role of the interneuron (association neuron) is to ________.

connect motor and sensory neurons in their pathways

What part of a neuron receives signals and sends a message to the cell body?

dendrite

The neuron processes that normally receive incoming stimuli are called ________.

dendrites

Unmyelinated nerve fibers are known as ________.

gray matter

When neurotransmitter molecules bind to receptors in the plasma membrane of the receiving neuron,

ion channels in the plasma membrane of the receiving neuron open.

The two major functional properties of neurons are ________.

irritability and conductivity

The gaps between Schwann cells are indicated by ________.

label H

Which of these is a deep pressure receptor?

lamellar corpuscle

Impulse conduction is fastest in neurons that are ________.

myelinated

Support cells in the central nervous system are collectively called ________.

neuroglia

A molecule that carries information across a synaptic cleft is a

neurotransmitter

The gaps between Schwann cells found at regular intervals in peripheral system neurons are called ________.

nodes of Ranvier

Which of these neuroglial cells forms the myelin sheath in the central nervous system?

oligodendrocytes

Cranial and Spinal Nerves

peripheral nervous system

communication lines with body

peripheral nervous system

During the resting state, a neuron is ________.

polarized with more sodium ions outside the cell and more potassium ions inside the cell

Sensory receptors located in muscles and tendons are termed ________.

proprioceptors

Which of the following is the correct sequence in a typical reflex arc?

receptor, sensory neuron, integration center, motor neuron, effector

Which of these lists the components of a reflex arc in the correct sequence?

receptor; afferent neuron; control center; efferent neuron; effector

Nerve impulse transmissions occurring along myelinated neurons are called ________.

saltatory conduction

An action potential is caused by an influx of these ions into the cell ________.

sodium

Which division of the peripheral nervous system activates skeletal muscles?

somatic nervous system

Fibers that carry information from the skin, joints, and skeletal muscles to the central nervous system are ________.

somatic sensory

The gap between two communicating neurons is termed ________.

synaptic cleft

The small space between the sending neuron and the receiving neuron is the

synaptic cleft

Neurons either conduct action potentials along the length of their axons, or they remain at rest. This statement best describes ________.

the all or none response

If a signal from a sending neuron makes the receiving neuron more negative inside,

the receiving neuron is less likely to generate an action potential.

When calcium ions enter the synaptic terminal,

they cause vesicles containing neurotransmitter molecules to fuse to the plasma membrane of the sending neuron.

Bundles of nerve fibers (neuron processes) running through the CNS are called ________, whereas in the PNS they are called ________.

tracts, nerves

Myelinated fibers (tracts) form ________ matter while unmyelinated fibers form ________ matter.

white, gray

At which membrane potential, given the graphs shown, do a sufficient number of the voltage-gated Na+ channels start to open?

-60 mV

What is the resting membrane potential of the neuron used in the experiment?

-80 mV

Which one of the following is the correct sequence of events that correlates to the sequence of events of a nerve impulse? 1. the membrane becomes depolarized 2. sodium channels open and sodium ions diffuse inward 3. the membrane becomes repolarized 4. potassium channels open and potassium ions diffuse outward while sodium is actively transported out of the cell

2,1,4,3

________ connect sensory and motor neurons in neural pathways and their cell bodies are typically located in the central nervous system.

Interneurons (association neurons)

Why is white matter "white"?

It contains a high concentration of myelin.

The neural processes that convey incoming messages toward the cell body are indicated by ________.

Label A

The axon is indicated by ________.

Label B

The axon terminals are indicated by ________.

Label C

The metabolic center of the neuron is indicated by ________.

Label D

The nucleus of the neuron is indicated by ________.

Label E

Functional nervous system division that carries information from the central nervous system toward effectors

Motor (efferent) Division

Structural nervous system subdivision that consists of spinal nerves and cranial nerves

Peripheral Nervous System (PNS)

________ cells form the myelin sheaths around nerve fibers in the PNS.

Schwann

Functional nervous system subdivision that carries information toward the central nervous system from receptors

Sensory (afferent) division

What is the first event of an action potential?

Sodium gates open and the membrane depolarizes.

The substance that is released at axonal endings to propagate a nervous impulse is called ________.

a neurotransmitter