NERVOUS SYSTEM: EXAM QUESTIONS

Cells within the CNS are missing the outer cell membrane of a Schwann cell are called

neurilemma Neurilemma are neurons within the CNS that have axons that are missing the outer cell membrane of a Schwann cells. This is necessary for the regeneration of nerve cells.

A neuron that transmits a nerve impulse toward the central nervous system is called a(n):

sensory neuron Sensory neurons transmit nerve impulses toward the central nervous system. Motor neurons transmit nerve impulses away from the central nervous system.

The part of the nervous system that transmits impulses from the CNS to skeletal (voluntary) muscle is the:

somatic nervous system The somatic nervous system is voluntary and transmits impulses from the central nervous system (CNS) to the skeletal muscle.

Cerebrospinal fluid circulates through the ventricles, into the central canal and ________, and is absorbed back into the blood.

subarachnoid space Cerebrospinal fluid circulates through the ventricles, into the central canal and subarachnoid space, and is absorbed back into the blood

The nerve commonly called the vagus nerve is the:

tenth cranial nerve The tenthcranial nerve, or the vagus, carries sensations and produces movements for the organs that it supplies. For example, it slows the heart, increases peristalsis, contracts muscles for voice production, and aids in the swallowing process.

Tic douloureux is a painful neuralgia of the __________nerve.

trigeminal Tic douloureux, also known as trigeminal neuralgia, causes pain that is due to compression or degeneration of the fifth cranial nerve, the trigeminal.

Which of the following is not a primary function of the cerebrum?

Appetite Willed movements, memory, and sensory perception are all primary functions of the cerebrum. Appetite is a function of the hypothalamus.

A synapse consists of: A. A synaptic knob B. A synaptic cleft C. The plasma membrane of a postsynaptic neuron D. All of the above

D. All of the above A synapse consists of a synaptic knob, a synaptic cleft, and the plasma membrane of a postsynaptic neuron. A synapse helps information move from one neuron to another.

Which of the following is not a function of the central nervous system (CNS)? A. Integrating sensory information B. Evaluating the information C. Initiating an outgoing response D. All of the above are functions of the CNS.

D. All of the above are functions of the CNS. The central nervous system integrates sensory information, evaluates it, and initiates an outgoing response.

A lack of this neurotransmitter is associated with Parkinson disease.

Dopamine A lack of dopamine is associated with Parkinson disease. Dopamine injections are ineffective treatment because dopamine cannot cross the blood-brain barrier and be absorbed by the brain tissue.

Ascending tracts conduct impulses from the brain.

False Ascending tracts conduct impulses up the cord to the brain, whereas descending tracts conduct impulses down the cord from the brain.

Gray matter is primarily cell bodies, interneurons, and myelinated fibers.

False Gray matter is primarily cell bodies, interneurons, and unmyelinated fibers.

Schwann cells are found throughout the nervous system. They support nerve fibers and sometimes form a myelin sheath around them.

False Schwann cells are found only in the peripheral nervous system.

The spinal cord is approximately 10 inches long and extends to the third lumbar vertebra.

False The spinal cord is approximately 17 to 18 inches long, and it extends from the foramen magnum to the bottom of the first lumbar vertebra.

The right and left hemispheres of the cerebrum specialize in different functions. This is known as convolution.

Fasle The right and left hemispheres of the cerebrum specialize in different functions, and this is known as hemisphericity. The left hemisphere specializes in language functions, and dominates the control of certain kinds of hand movements. The right hemisphere is responsible for the perception of certain kinds of auditory material, tactile perception, and perceiving and visualizing spatial relationships.

Several vital centers are located in the:

Medulla Several vital centers—cardiac, respiratory, and vasomotor—are located in the medulla.

Which type of cell specializes in acting as a microbe-eating scavenger?

Microglia Microglia surround microbes, draw them into their cytoplasm, and digest them by phagocytosis.

Which of the following most accurately describes the kind of fibers found in spinal nerves?

Motor and sensory fibers Spinal nerves contain sensory fibers, which bring sensory information from the body to the central nervous system (CNS), and motor fibers, which bring information from the CNS to the muscles of the body.

The neural pathway involved in the patellar, or "knee jerk," reflex is known as the ____________ (2 words).

Reflex arc Impulse conduction by a reflex arc causes a reflex to occur. In a patellar, or "knee-jerk," reflex the nerve impulses that reach the quadriceps muscle result in the patellar, or "knee-jerk," response.

The myelin sheath is formed by:

Schwann cells The myelin sheath is formed by the Schwann cells in the peripheral nervous system. In the central nervous system, the myelin sheath is formed by the oligodendrocytes.

Impulses from the _________ play a part in arousing or alerting the cerebrum.

Thalamus Impulses from the thalamus play a part in arousing or alerting the cerebrum. The thalamus also serves as a sensory relay station from various body areas to the cerebral cortex. You should review Diencephalon.

There are ______ pairs of spinal nerves.

There are 31pairs of spinal nerves.

Which of the following is not a plexus of the spinal nerves?

Thoracic As spinal nerves exit from the vertebral column, sometimes nerve fibers from several spinal nerves are reorganized to form a single peripheral nerve. This reorganization can be seen as a network of intersecting branches called a plexus.The four major spinal plexuses are cervical, brachial, lumbar, and sacral. You should review Spinal Nerves.

Acetylcholine is a small-molecule neurotransmitter that is found in various locations in the nervous system.

True Acetylcholine is a small-molecule neurotransmitter that is found in various locations in the nervous system. It has both an excitatory effect and inhibitory effect depending on the location where it is functioning.

Bundles of fibers, called fascicles, are held together by a layer of connective tissue layer called the perineurium.

True Bundles of fibers, called fascicles, are held together by a layer of connective tissue layer called the perineurium. Numerous fascicles are then held together to form a complete nerve by a fibrous layer called the epineurium.

A membrane that exhibits a membrane potential is said to be polarized and can be measured by a device called a voltmeter.

True A membrane that exhibits a membrane potential is said to be polarized. It has a negative and a positive pole. The magnitude of potential difference between the two sides of a polarized membrane is measured in volts (V) or millivolts (mV) and can be measured by a device called a voltmeter.

The pineal gland secretes melatonin, which is the "timekeeping hormone."

True The pineal gland secretes the hormone melatonin. High blood levels of melatonin signal the body that it is time to sleep so this hormone is sometimes referred to as the "timekeeping hormone." You should review Diencephalon.

A synaptic knob would be located on a(n):

axon A synaptic knob, which is a tiny bulge at the end of a terminal branch of a presynaptic neuron's axon, is located on an axon.

The main divisions of the central nervous system are the:

brain and spinal cord The central nervous system is made up of the brain and spinal cord. The CNS, as its name implies, is centrally located in the body.

A mixed nerve is one that:

carries both sensory and motor fibers A mixed nerve carries both sensory and motor fibers. All spinal nerves contain both motor and sensory fibers and are therefore mixed nerves.

Dopamine, norepinephrine, and epinephrine are neurotransmitters that are classified as:

catecholamines Dopamine, norepinephrine, and epinephrine are classified as catecholamines. Catecholamines are a group of compounds that may play a role in sleep, motor function, mood, and pleasure recognition.

Cerebrospinal fluid is formed by filtration of blood in the:

choroid plexus Cerebrospinal fluid is formed by the filtration of blood in the choroid plexus. Cerebrospinal fluid removed through a lumbar puncture can be tested for the presence of blood cells, bacteria, or other abnormal characteristics that may indicate an injury or infection.

A common type of traumatic brain injury resulting from a jolt to the head is:

concussion A concussion is a common example of traumatic brain injury resulting from a jolt to the head that bends the brainstem and causes temporary chemical changes in the brain.

Somatic responses consist of:

contractions of skeletal muscles Somatic responses are voluntary and consist of skeletal muscle contractions.

The cerebellum performs all of the following functions except:

controlling cardiac function The cerebellum coordinates control of muscle action, helps control posture, and controls skeletal muscles to maintain balance.

Along a neuron, the correct pathway for impulse conduction is:

dendrite, cell body, and axon The correct pathway for impulse conduction is dendrite to cell body to axon. Dendrites receive impulses and transmit them toward the cell body. Impulses are then transmitted away from the cell body by the axon.

The abducens cranial nerve innervates:

eye movements The abducens cranial nerve is a motor nerve that controls one of the extrinsic eye movements.

Which of the following cranial nerves is responsible for movements of the tongue?

hypoglossal The hypoglossal cranial nerve is responsible for movements of the tongue. Hypo means ?under? and gloss means ?tongue.? This nerve runs under the tongue.

The part of the brain that can influence the release of hormones of the endocrine system is the:

hypothalamus The part of the brain that can influence the release of hormones of the endocrine system is the hypothalamus. It assists with the regulation of body temperature, water balance, sleep-cycle control, appetite, and sexual arousal.

Interneurons reside:

in the CNS only Interneurons are located in the central nervous system only.

Paralysis of both legs is called:

paraplegia Paraplegiais paralysis of both legs; hemiplegia is paralysis of one entire side of the body. Triplegia is the paralysis of both legs and one arm, and quadriplegia is the paralysis of all four extremities.

Cranial nerves are part of the:

peripheral nervous system (PNS) There are 12 pairs of cranial nerves that are attached to the undersurface of the brain and are part of the peripheral nervous system.

The innermost layer of the meninges is the:

pia mater The pia mater is the innermost layer of the meninges. It covers the brain and spinal cord and means "soft or gentle mother."