Nervous System

There are ________ pairs of cranial nerves and ________ pairs of spinal nerves in the peripheral nervous system.

12; 31

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

The gaps between Schwann cells are indicated by ________.

Label H

________ disease results from a degeneration of the dopamine-releasing neurons of the substantia nigra.

Parkinson's

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

Schwann

________ reflexes include the secretion of saliva, changes in the size of our pupils, and digestion involve the activities of smooth muscles.

autonomic

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

axon

One of the major functions of the pons is to control ________.

breathing

Ganglia are collections of ________.

cell bodies

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

central; peripheral

Loss of muscle coordination results from damage to the ________.

cerebellum

Hemiplegia and aphasia characterize those patients who have experienced a ________.

cerebrovascular accident (CVA), or stroke

The brain dysfunction where blood supply to a region (or regions) of the brain is blocked and vital brain tissue dies, as by a blood clot or a ruptured blood vessel, is called ________.

cerebrovascular accident (CVA), or stroke

Which one of the following is the correct sequence of nerves that exit the spinal cord, from superior to inferior?

cervical spinal nerves, thoracic spinal nerves, lumbar spinal nerves, sacral spinal nerves

The large fiber tract that allows communication between the two cerebral hemispheres is called the ________.

corpus callosum

Which one of the following statements about aging is most accurate?

despite some neuronal loss, an unlimited number of neural pathways are available and ready to be developed; therefore, additional learning can occur throughout life

The thalamus, hypothalamus, and epithalamus collectively constitute the ________.

dicephalon (interbrain)

Bipolar neurons are commonly ________.

found in the eye and nose

Unmyelinated nerve fibers are known as ________.

gray matter

One of the last areas of the CNS to mature is the ________, which regulates body temperature.

hypothalamus

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

interneurons (association neurons)

The fissure in the brain that separates the two cerebral hemispheres is called the ________.

longitudinal fissure

The brain and spinal cord are protected and cushioned by three connective tissue membranes that are collectively called ________.

meninges

Neurons with several processes branching off the cell body, such as motor neurons and interneurons (association neurons), are structurally classified as ________.

multipolar

Impulse conduction is fastest in neurons that are ________.

myelinated

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

neuroglia

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

nodes of ranvier

The ________ division of the autonomic nervous system is often called the "rest-and-digest" division.

parasympathetic

The primary somatic sensory cortex is located in the ________ lobe of the cerebrum.

parietal

The ________ is a connective tissue wrapping around fascicles of neuron fibers.

perineurium

The delicate innermost membrane, or meningeal layer, that clings to the surface of the brain and spinal cord is known as the ________ mater.

pia

The hypothalamus regulates the ________.

pituitary gland

During repolarization, ________ ions are pumped out of the cell.

potassium

Sensory receptors located in muscles and tendons are termed ________.

proprioceptors

Each spinal nerve divides into a dorsal and a ventral ________.

ramus

The largest nerve in the body, the sciatic nerve, belongs to the ________ nerve plexus.

sacral

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

sodium

What congenital disorder results when the vertebrae fail to form completely around the spinal cord, typically in the lumbosacral region?

spina bifida

Sweat glands that produce perspiration when stimulated are innervated only by the ________ fibers.

sympathetic

The gap between two communicating neurons is termed ________.

synaptic cleft

The portion of the diencephalon that acts as a relay station for sensory impulses traveling to the sensory cortex is the ________.

thalamus

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

tracts; nerves

The number of neurons involved in transmission of impulses in the autonomic nervous system is ________.

two

The only pair of cranial nerves to extend to the thoracic and abdominal cavities is the ________ nerves.

vagus

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

white; gray