Nerve MCQs

1. NerveMCQs

2. A neuron generally has all of the following principle areas except • microvilli. • a cell body. • dendrites. • an axon.

3. Which of the following is not a function of neurons? Respond to physical and chemical stimuli. Conduct electrical impulses. Release specific chemical regulators. All of these are neuron functions.

4. A grouping of cell bodies located within the central nervous system is known as a • tract. • nerve. • nucleus. • ganglion.

5. Involuntary effectors (glands, smooth or cardiac muscle) are innervated (stimulated by) • autonomic neurons. • efferent neurons. • motor neurons. • association neurons.

6. A grouping of cell bodies located within the central nervous system is known as a • bipolar • multipolar • pseudounipolar

7. Myelin sheaths around axons located within the CNS are formed by Schwann cells. microglia. astrocytes. oligodendrocytes.

8. Which of the following cell types is not a supporting cell or glial cell of the nervous system? Schwann cell oligodendrocyte astrocyte. association neuron

9. The glial cells in the CNS which are capable of phagocytosis are astrocytes. oligodendrocytes. satellite cells. microglia.

10. Within the central nervous system astrocytes are responsible for myelinateing axons. producing cerebrospinal fluid. phagocytizing particulate matter. aid in synapse formation.

11. In the absence of stimuli, all cells in the body maintain a potential difference across the membrane called the _____, in which the inside of the cell is negatively charged in comparison to the outside of the cell. • action potential • threshold potential • resting membrane potential • graded potential

12. The term "voltage regulated" means that the membrane • voltage gated ion channels open and close with changes in the membrane potential. • potential is controlled by the Na+/K+ pumps. • gates will not respond unless the voltage is "regular." • potential can only be controlled by an oscilloscope.

13. The diffusion of K+ out of the cell makes the inside of the cell less positive, or more negative, and acts to restore the original resting membrane potential -a process called • depolarization. • hyperpolarization. • repolarization. • overshoot.

14. Both the depolarization and repolarization changes that occur during the action potential are produced by • simple diffusion of ions down their concentration gradients. • active transport pumps along the neuron membrane. • negative feedback loops. • carrier mediated transport.

15. Nerve impulses (action potentials) are conducted along an axon without decrement. This means the action potentials are conducted without • decreasing velocity. • altering the threshold potential. • decreasing amplitude. • altering the Na+ or K+ concentrations in the neuron.

16. Which of the following is not a neuron-neuron synapse? • neuromuscular junction • axosomatic synapse • axoaxonic synapse • dendrodentritic synapse

17. Electrical synapses occur when two cells are joined by integrin proteins. are characterized by a synaptic cleft. occur between two cells of unequal size. require the presence of gap junctions.

18. The small membrane-enclosed compartments that hold and release the neurotransmitter molecules from within the presynaptic neuron, are called • synaptic vesicles. • synaptic clefts. • terminal boutons. • gap junctions.

19. As the intensity of the stimulus in a presynaptic neuron increases, the number of vesicles undergoing exocytosis ___, and the number of released neurotransmitter molecules ____. • increases; increases • increases; decreases • decreases; increases • decreases; decreases

20. The blood-brain barrier is composed of two cells types, endothelial cells and oligodendrites microglia Schwann cells astrocytes