Chapter 11/12: Exam 3

What is the primary function of the sensory division of the peripheral nervous system?

• To send motor commands to muscles

• To detect stimuli and send information to the CNS

• To integrate information within the brain

• To regulate hormone secretion

Which part of the nervous system contains the brain and spinal cord?

• Peripheral nervous system

• Central nervous system

• Autonomic nervous system

• Somatic nervous system

Which type of neuron has one axon and multiple dendrites?

• Bipolar neuron

• Pseudounipolar neuron

• Multipolar neuron

• Unipolar neuron

What type of neuroglial cell myelinates axons in the peripheral nervous system?

• Astrocytes

• Oligodendrocytes

• Microglia

• Schwann cells

During the action potential, what causes the rapid depolarization phase?

• Opening of voltage-gated potassium channels allowing K+ to exit

• Closing of sodium channels preventing Na+ entry

• Opening of voltage-gated sodium channels allowing Na+ to enter

• Efflux of chloride ions causing hyperpolarization

Which of the following best explains the function of astrocytes in the CNS?

• Myelinate multiple axons to increase signal speed

• Act as phagocytes removing cellular debris

• Form the blood-brain barrier and regulate extracellular fluid

• Line the brain ventricles and circulate cerebrospinal fluid

What structural feature of pseudounipolar neurons enables rapid transmission of sensory information?

• Multiple dendrites that receive inputs

• A single short process splitting into two axons

• Presence of numerous synaptic terminals

• Large cell body containing multiple nuclei

During the relative refractory period, why is it more difficult to generate a new action potential?

• Sodium channels are completely inactive

• Potassium channels remain open, hyperpolarizing the membrane

• The membrane potential is at its most positive

• Calcium influx prevents depolarization

What is the term for the electrical charge difference across a cell membrane when the cell is at rest?

• Action potential

• Resting membrane potential

• Threshold potential

• Refractory period

Which neuroglial cell type acts as the immune defense in the CNS by engulfing pathogens?

• Oligodendrocytes

• Microglial cells

• Astrocytes

• Satellite cells