3. From the list of terms that follow, please label the figure (at least once) b accordingly . . . . . Axon Na Inactive Closed Polarized . Re-polarized • De-polarized • Propagation Using the diagram below, in 2-4 sentences, explain how a signal moves down the axon in one direction. • what causes the threshold potential to arrive/occur? VEC

3. From the list of terms that follow, please label the figure (at least once) b accordingly . . . . . Axon Na Inactive Closed Polarized . Re-polarized • De-polarized • Propagation Using the diagram below, in 2-4 sentences, explain how a signal moves down the axon in one direction. • what causes the threshold potential to arrive/occur? VEC

Biology: The Dynamic Science (MindTap Course List)

4th Edition

ISBN:9781305389892

Author:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Publisher:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Chapter39: Information Flow And The Neuron

Section: Chapter Questions

Problem 6TYK: In the propagation of a nerve impulse: a. the refractory period begins as the K+ channel opens,...

See similar textbooks

Similar questions

In the propagation of a nerve impulse: a. the refractory period begins as the K+ channel opens, allowing K+ ions to flow outward along their concentrationgradient. b. Na+ ions flow out of the axon with their concentration gradient. c. positive charges lower the membrane potential to its lowestaction potential. d. gated K+ channels open at the same time as the activationgate of Na+ channels closes. e. the depolarizing stimulus lowers the membrane potential toopen the Na+ gates.
Which of the following is probably going to propagate an action potential fastest? a thin, unmyelinated axon a thin, myelinated axon a thick, unmyelinated axon a thick, myelinated axon
View the University of Michigan Webscope (http://openstaxcollege.org/l/nervefiber) to see an electron micrograph of a cross-section of a myelinated nerve fiber. The axon contains microtubules and neurofilaments, bounded by a plasma membrane known as the axolemma. Outside the plasma membrane of the axon is the myelin sheath, which is composed of the tightly wrapped plasma membrane of a Schwann cell. What aspects of the cells in this image react with the stain that makes them the deep, dark, black color, such as the multiple layers that are the myelin sheath?
An example of a synapse could be the site where: a. neurotransmitters released by an axon travel across a gap and are picked up by receptors on a muscle cell. b. an electrical impulse arrives at the end of a dendrite causingions to flow onto axons of presynaptic neurons. c. postsynaptic neurons transmit a signal across a cleft to apresynaptic neuron. d. oligodendrocytes contact the dendrites of an afferent neurondirectly. e. an onoff switch stimulates an electrical impulse in apresynaptic cell to stimulate other presynaptic cells.
Which of the following statements best describes saltatory conduction? a. It inhibits direct neurotransmitter release. b. It transmits the action potential at the nodes of Ranvier andthus speeds up impulses on myelinated axons. c. It increases neurotransmitter release at the presynapticmembrane. d. It decreases neurotransmitter uptake at chemically gatedpostsynaptic channels. e. It removes neurotransmitters from the synaptic cleft.
1. Action potentials are generated in a region called the _______ which includes the axon hillock and the initial segment of the axon. 2.According to the all-or-nothing principle a.once the electrical impulse reaches a certain level of intensity (its threshold), it fires and moves all the way down the axon without losing any intensity. b.the amount of time a neuron must “rest” in between firing episodes is stable. c.as a person ages, his or her neurological system slows down and the intensity of neural impulses decreases significantly. d.if all the neurons in a network are not integrated, the “message” carried by the neurons will be lost.
4. What are the problems with a repaired PNS axon? 5. Identify the kind of neuronal pool based on the information provided.a. Several presynaptic neurons synapse on the same postsynaptic neuron giving strong excitation or inhibition.b. Input neuron stimulates several pathways which stimulate the output neuron to go on firing for a longer time after input has truly stopped. c. On presynaptic neuron synapses on 2 or 3 postsynaptic neurons and these postsynaptic neurons (now presynaptic ) synapse on another 2 or 3 postsynaptic neurons.d. Neurons stimulate each other in a linear sequence but one cell restimulates the first cell (presynaptic neuron) to start the process all over again. e. This neuron pool is common in the withdrawal reflex. f. Diaphragm and rib muscles both under subconscious control, but can be consciously overridden when holding your breath.g. Pain information spreads quickly into multiple areas of CNS.h. Major type pathway in short-term memory
1. If a single axon is firing at maximum frequency, how does the nervous system know if the stimulus increases further? 2. At maximal stimulation, much above the threshold, how long will it be until an axon fires the next AP? a.The absolute refractory period b.The relative refractory period c.The absolute and relative refractory periods On what part of the neuron are NT receptors typically located? If the activated NT receptors cause channels to open or change thus changing the diffusion of ions, what type of potential will this initially produce A. Resting B. Graded, C.Action, D.Homeostatic
1. Why does the action potential not go back to where it came from? (Multiple answers possibly) the absolute refractory period prevents this from happening Sodium voltage gated ions in the area where the action potential just came from are fully activated or inactivated Sodium voltage gated ions bind to the Na+ ions, preventing them from diffusing backwards Na+ only diffuses forward in the axon 2. When neurotransmitter binds to _______________ at the dendrites, it results in a _____________ potential Ligand gated ion channels | action Voltage gated ion channels | action Voltage gated ion channels | graded Ligand gated ion channels | graded
13. The entry of sodium into the axon causes A. Depolarization of the membrane B. Increase negativity inside the axon C. The refractory period D. A resting potential
Ordinarily, a neuron’s trigger zone is activated before any other part ofan axon, so a wave of action potentials occurs as sodium channelsopen in the direction of the synaptic terminal. What would happen ifyou artificially stimulated an axon to reach threshold potential midwayalong its length rather than at the trigger zone?a. Action potentials would occur in the direction of the synapticterminal.b. No action potentials would occur.c. Action potentials would occur in the direction of the trigger zone.d. Both a and c are correct.
1) The interior of an axon at rest is negatively charged relative to the outside is positively charged relative to the outside has the same charge as the outside has the same concentration of potassium (K+) as the outside 2) The branch-like portions of a neuron that carries information toward the cell body is the axon. dendrite. terminal button. soma.