EXAM WITH CORRECT SOLUTIONS.

• | Page

NURS 617 EXAM 3

EXAM WITH CORRECT SOLUTIONS.

Functions of the nervous system (4) - correct answer- - Detecting, analyzing and transmitting information

• Provides foundation for intelligence, anticipation, and

judgment

• Controls skeletal muscle movement
• Helps to regulate cardiac and visceral smooth activity

Definition of Neurons - correct answer- functional cells that conduct impulses to other nerve cells, muscles, or gland cells

Three parts of a neuron - correct answer- cell body, dendrites, axon

What does the cell body do? - correct answer- - Soma- nucleus- DNA and genetic codes

• Cell activity
• Metabolic activities

• / 4

• | Page

What do dendrites do? - correct answer- conduct info to cell body § Extension of cell body that brings info into the cell body

What does the axon do? - correct answer- Long projections from the cell body (normally only one) that pass nerve impulses

Function of neuroglial cells - correct answer- - provide protection, regulate blood flow and metabolic support for the neurons

• Form the myelin sheath from oligodendrocytes and Schwan

cells § Helps with the transmission of electrical impulses along the nerve cells

Neuroglial cells of the central nervous system - correct answer- oligodendrocytes

Neuroglial cells of the peripheral nervous system - correct answer- Satellite

• / 4

• | Page

What do astrocytes do? - correct answer- help to form the blood-brain barrier, which prevents the entrance of toxic materials from the blood to the brain

Major fuel source for the brain? - correct answer- Glucose

Afferent - correct answer- sensory- transmit information to the CNS

Efferent - correct answer- Motor carry information away from the CNS

Retrograde - correct answer- axon to cell body

Anterograde - correct answer- cell body to axon

Resting membrane potential - correct answer- polarized (no electrical activity occurs = -70 mV) § Positive outside/ negative inside

• / 4

• | Page

Depolarization - correct answer- sodium channels open- generate electrical impulse= +30 mV) § Negative outside/ positive inside

Repolarization - correct answer- permeable to potassium- exit of K-return to resting membrane potential)

• Na close and K open

Absolute refractory - correct answer- The minimum length of time after an action potential during which another action potential cannot begin.

relative refractory period - correct answer- a stronger than usual stimulus is necessary to initiate an action potential

electrical synaptic transmission - correct answer- gap junctions- action potentials move rapidlY

Pathway of chemical synaptic transmission - correct answer- presynaptic release of chemical messenger (neurotransmitters)

• / 4