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Download Baypath-Bio151-Exam1 Exam 1 BAY PATH ANATOMY AND PHYSIOLOGY II FALL2017 Name___________________________________ MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The ________ division carries signals to the smooth muscle in the large intestine. 1) _______ A) visceral motor B) somatic sensory C) afferent D) somatic motor E) visceral sensory 2) Which of the following are effectors? 2) _______ A) Receptors B) Reflexes C) Sense organs D) Glan ds E) Stimuli 3) What is another name for the autonomic nervous system? 3) _______ A) Somatic sensory division B) Visceral sensory division C) Central nervous system D) Somatic motor division E) Visceral motor division 4) Some ________ neurons are specialized to detect stimuli, whereas ________ neurons 4) _______ send signals to the effectors of the nervous system. A) afferent; inter- B) afferent; efferent C) motor; sensory D) efferent; afferent E) efferent; inter- 5) What is the most common type of neuron? 5) _______ A) Dendritic B) Multipolar C) Anaxonic D) Unipolar E) Bipolar 6) The term "nerve fiber" refers to a(n) ________. 6) _______ A) nerve cell B) bundle of macromolecules in nerve cells C) organelle in nerve cells D) axon E) organ 7) Which glial cell is found wrapped around nerve fibers in the PNS? 7) _______ A) Schwann cells B) Oligodendrocytes C) Nodes of Ranvier D) Satellite cells E) Ependymal cells 8) What is the primary site on a neuron for receiving signals from other neurons? 8) _______ A) The axons B) The neurosomas C) The axon terminals D) The axon collaterals E) The dendrites 9) Which cells form myelin in the spinal cord? 9) _______ A) Oligodendrocytes B) Microglia C) Satellite cells D) Astrocytes E) Schwann cells 10) In a neuron, the opening of sodium gates typically leads to ________. 10) ______ A) repolarization of the plasma membrane B) hyperpolarization of the plasma membrane C) plasma membrane voltage returning to the resting membrane potential D) depolarization of the plasma membrane E) drifting of plasma membrane voltage toward a more negative value 11) Which of the following will cause the plasma membrane to hyperpolarize when at its 11) ______ RMP? A) An inflow of potassium B) An outflow of chloride C) An inflow of sodium D) An inflow of chloride E) An inflow of calcium 12) An inhibitory local potential causes which of the following? 12) ______ A) Hyperpolarization of the plasma membrane B) Repolarization of the plasma membrane C) Neutralization of the plasma membrane D) Depolarization of the plasma membrane E) Drifting of the membrane potential towards the resting membrane potential 13) Local potentials are ________, whereas action potentials are ________. 13) ______ A) irreversible; reversible B) produced by voltage-regulated channels; produced by gated channels C) graded; all or none D) nondecremental; decremental E) self -propagating; local 14) During the absolute refractory period which of the following is true? 14) ______ A) The neuron fires at its maximum voltage if a stimulus depolarizes the neuron to threshold. B) If a neuron reaches threshold, the action potential goes to completion. C) The signal grows weaker with distance. D) No stimulus of any strength will trigger a new action potential. E) It is possible to trigger a new action potential, but only with an unusually strong stimulus. 15) A cholinergic synapse uses ________ as its neurotransmitter. 15) ______ A) epinephrine B) monoamine C) acetylcholine D) catecholamine E) norepinephrine 16) What is the most common inhibitory neurotransmitter in the brain? 16) ______ A) Epinephrine B) Norepinephrine C) γ -aminobutyric acid (GABA) D) Acetylcholine E) Noradrenaline 17) Which of these is an example of an EPSP in a typical neuron? 17) ______ A) A voltage change from -70 mV to -70.5 mV B) A voltage change from -69.5 mV to -70 mV C) A voltage change from +35 mV to 0 mV D) A voltage change from 0 mV to +0.35 mV E) A voltage change from -70 mV to -69.5 mV 18) Parkinson disease is a progressive loss of motor function due to the degeneration of 18) ______ specific neurons. These neurons secrete an inhibitory neurotransmitter that prevents excessive activity in motor centers of the brain. What neurotransmitter is this? A) Serotonin B) Glutamate C) Acetylcholine D) GABA E) Dopamine 19) Where does saltatory conduction occur? 19) ______ A) From node to node in myelinated fibers B) Down the entire length of an unmyelinated fiber C) Down the entire length of a myelinated fiber D) From node to node in unmyelinated fibers 20) Place the following events in synaptic transmission at a cholinergic synapse in 20) ______ order: A - A postsynaptic potential is produced; B - Voltage gated calcium channels open and calcium enters the cell; C - ACh is released and diffuses across the axon terminal; D - A nerve signal arrives at an axon terminal; E - Ligand gated sodium channels open and sodium enters the cell. A) B, C, D, E, A B) D, B, C, E, A C) B, D, C, A, E D) D, B, E, A, C 21) Many upper motor neurons synapse with lower motor neurons in the ________. 21) ______ A) anterior horn B) anterior column C) posterior root ganglion D) posterior column E) posterior horn 22) Which of the following is not considered a region of the spinal cord? 22) ______ A) Pelvic B) Cervical C) Thoracic D) Sacral E) Lumbar 23) Which of the following fractures would be the least likely to cause a spinal cord injury? 23) ______ A) A fracture of vertebra T5 B) A fracture of vertebra T12 C) A fracture of vertebra L4 D) A fracture of vertebra C2 E) A fracture of vertebra C6 24) The middle layer of the meninges is called the ________. 24) ______ A) dura mater B) white matter C) arachnoid mater D) gray matter E) pia mater 25) Epidural anesthesia is introduced to the epidural space between the ________ to block 25) ______ pain signals during pregnancy. A) dura mater and arachnoid mater B) arachnoid mater and pia mater C) dura mater and pia mater D) dural sheath and vertebral bones E) dural sheath and dura mater 26) Voluntary motor impulses leave the spinal cord via the ________ of gray matter. 26) ______ A) lateral horn B) anterior column C) anterior horn D) posterior horn E) posterior column 27) Cerebrospinal fluid fills the space between the ________. 27) ______ A) arachnoid mater and pia mater B) dural sheath and dura mater C) dura mater and arachnoid mater D) dural sheath and vertebral bones E) dura mater and pia mater 28) Whic h of the following is contained within gray matter? 28) ______ A) Neurosomas, dendrites, and proximal parts of axons of neurons B) Glial cells and myelinated fibers C) The distal part of axons of lower order motor neurons D) Glial cells, axons of motor neurons, and Schwann cells E) Glial cells only 29) Motor commands are carried by ________ from the brain along the spinal cord. 29) ______ A) spinal nerves B) cranial nerves C) both anterior and posterior roots D) descending tracts E) ascending tracts 30) Second -order neurons synapse with third-order neurons in the ________. 30) ______ A) cerebral cortex B) medulla oblongata C) dorsal root ganglion D) thalamus E) spinal cord 31) A ganglion is a ________. 31) ______ A) bundle of axons in the PNS B) cluster of neurosomas in the PNS C) bundle of axons in the CNS D) cluster of dendrites in either the CNS or the PNS E) cluster of neurosomas in the CNS 32) There are ________ pairs of spinal nerves. 32) ______ A) 35 B) 12 C) 24 D) 62 E) 31 33) The connective tissue that surrounds a nerve fascicle is called the ________. 33) ______ A) epineurium B) perimysium C) perineurium D) myelin E) endoneurium 34) A patient with no sensation in the left thumb would most likely have nerve damage of 34) ______ the ________ spinal nerve. A) C5 B) T5 C) L3 D) C6 E) T1 35) A mixed nerve consists of both ________ and ________. 35) ______ A) interneurons; efferent neurons B) glial cells; nerve cells C) afferent; efferent fibers D) spinal; cranial fibers E) myelinated; unmyelinated fibers 36) The bundle of nerve roots that occupy the vertebral canal from L2 to S5 is called the 36) ______ ________. A) cervical enlargement B) lumbar enlargement C) spinal cord D) medullary cone E) cauda equina 37) Which one of the following best describes the order of a somatic reflex? 37) ______ A) Somatic receptor → afferent nerve fiber → interneuron → efferent nerve fiber → smooth muscle B) Somatic receptor → efferent nerve fiber → interneuron → afferent nerve fiber → skeletal muscle C) Somatic receptor → afferent nerve fiber → interneuron → efferent nerve fiber → skeletal muscle D) Somatic receptor → interneuron → afferent nerve fiber → efferent nerve fiber → skeletal muscle E) Somatic receptor → efferent nerve fiber → afferent nerve fiber → interneuron → skeletal muscle 38) A reflex in which the sensory input and motor output are on opposite sides of the spinal 38) ______ cord, is called a(n) ________ reflex arc. A) intersegmental B) monosynaptic C) ipsilateral D) polysynaptic E) contralateral TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false. 39) Nerve fibers in a given white matter tract are similar in origin, destination, and function. 39) ______ 40) Ascending signals in the spinal cord travel via gray matter, while descending signals 40) ______ travel via white matter. 41) The cerebellum is the largest part of the brain. 41) ______ 42) Purkinje cells are unusually large neurons found in the cerebellum. 42) ______ MULTIPLE CHOICE.
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