SOLVED

41) Kristine suffers from _________________, which is associated with the myelin sheaths surrounding neurons being “eaten away” and neural messages not fully travelling down axons. a. multiple sclerosis b. cystic fibrosis c. Parkinson’s disease d. Alzheimer’s disease 42) The ________ speeds up the passage of electrical messages by acting as an insulator of the neuronal signal. a. terminal button b. myelin sheath c. blood-brain barrier d. All of the answers are correct. 43) The action potential causes neurotransmitters to be released into the a. myelin sheath. b. axon. c. synapse. d. synaptic vesicle. 44) Scientists have been able to record the electrical activity of neurons using a. tiny electrodes. b. single cell stimulation. c. event related potentials (ERPs). d. functional magnetic resonance imaging (fMRIs). 45) During an action potential, what changes are evident in the negative ions inside the neuron? a. Negative ions rush out of the axon to increase the positive charge inside the axon. b. Negative and positive ions flow into the axon to maintain a balanced proportion. c. There is little or no net change in the distribution of negative ions. d. Negative ions trigger the release of neurotransmitters in the axon terminals. 46) What is the threshold level needed to trigger an action potential in many neurons? a. -70 mV b. -55 mV c. 0 mV d. +40 mV 47) During the refractory period, the electrical charge inside the cell is _____________ the electrical charge when the cell is in a resting state. a. more positive than b. larger than c. more negative than d. smaller than 48) The voltage of -60 mv is known as the neuron’s a. postsynaptic potential. b. graded potential. c. action potential. d. resting potential. 49) When a cell is “at rest,” it is in a state called the a. stopping point. b. obcipitation junction. c. resting potential. d. action potential. 50) When the electric potential in a cell is in action versus a resting state, this electrical charge reversal is known as the a. resting potential. b. excitation reaction. c. action potential. d. permeable reaction.