A&P Ch 7 The Nervous System

The axon of a neuron __________.

Conducts nerve impulses away from the neuron cell body

Which of the following effects is characteristic of the parasympathetic nervous system?

Decreased heart rate

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

Dendrite

Together with the brain stem, the __________ oversees all subconscious, autonomic functions.

Diencephalon

The cell bodies of sensory neurons whose fibers enter the spinal cord are found in the __________.

Dorsal root ganglia

Which of the following substances is/are NOT prevented from entering brain tissue due to the tight junctions that form the blood-brain barrier?

Essential amino acids

Bipolar neurons are commonly ________.

Found in the eye and nose

What is the first event of an action potential?

Sodium gates open and the membrane depolarizes.

__________ reflexes regulate skeletal muscle.

Somatic

Which division of the peripheral nervous system activates skeletal muscles?

Somatic nervous system

The gap between two communicating neurons is termed ________.

Synaptic cleft

Cranial nerve III is known as the ________ nerve.

optic oculomotor

Which of the following statements regarding the nerve impulse is TRUE?

A stimulus changes the permeability of a "patch" of the membrane, and sodium ions (Na+) diffuse rapidly into the cell.

__________ neurons carry an impulse to the CNS.

Afferent

Which of the following can adversely affect brain development?

Alcohol

The __________ produce cerebrospinal fluid.

Choroid plexuses

An action potential i) occurs when the graded potential is strong enough, ii) obeys the all-or-none rule, iii) is initiated by the opening of "gates" for sodium channels, iv) is characterized by a series of depolarizations/repolarizations along the membrane.

All the statements are correct.

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

Which of the following conditions would result from damage to the cerebellum?

Ataxia

The cerebellum aids in maintenance of __________.

Balance and posture

The term central nervous system refers to the ________.

Brain and spinal cord

The midbrain, pons, and medulla oblongata are housed in the ________.

Brainstem

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

Breathing

Sally has a brain injury; she knows what she wants to say but can't vocalize the words. The part of her brain that deals with the ability to speak is the ________.

Broca's area

The __________ nervous system includes the brain and spinal cord.

Central

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

Central; peripheral

Which spinal plexus gives rise to the phrenic nerve, and what organ does this nerve supply?

Cervical; diaphragm

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

Hypothalamus

Why is white matter "white"?

It contains a high concentration of myelin.

Physicians can use simple reflex tests to monitor the CNS. When reflex tests are abnormal, more sophisticated neurological tests may be ordered to try to localize and identify the problem. What is an electroencephalogram (EEG)?

It is a tool that measures the patterns of electrical activity of the neurons in the brain.

Which of these is a deep pressure receptor?

Lamellar corpuscle

The three connective tissue membranes covering and protecting CNS structures are collectively known as the __________. The __________ is the outermost, leathery layer.

Meninges; dura mater

Spinal nerves are _____ nerves.

Mixed

The nervous system gathers and interprets information, and then effects a response through a process called __________.

Motor output

All motor and association neurons are __________.

Multipolar

Impulse conduction is fastest in neurons that are ________.

Myelinated

Between successive Schwann cells, there are gaps in the myelin sheath called __________.

Nodes of Ranvier

The effects of the sympathetic nervous system are essentially opposite of the ________.

Parasympathetic nervous system

The deep groove that separates the two hemispheres of the cerebrum is called the __________.

Periosteum; dura mater

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

Potassium

What part of the brain do we use when initiating skeletal muscle movement?

Primary motor area

The corpus callosum connects the __________.

Right and left cerebral hemispheres

Anesthetics work by blocking the movement of an ion into an axon, thus preventing an action potential from being generated. Which ion is being blocked?

Sodium

Which of the following statements regarding the brain stem is FALSE?

The medulla oblongata plays a role in regulating the pituitary gland.

Which statement describes a function of the spinal cord?

The spinal cord sends sensory information to the brain and carries motor signals from the brain to motor neurons.

What cranial nerve pair supplies many organs in the ventral body cavity?

Vagus nerves

The hypothalamus regulates the ________.

pons pituitary gland

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

ramus tract

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

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