One of the characteristics of botulinum toxin (the cause of 'botulism') is a very specific protease activity, i.e., the toxin can cleave (cut), and thereby render nonfunctional, a SNARE protein associated with neurotransmitter-containing synaptic vesicles found in certain nerve terminals. Which of the following is the likely effect of this toxin on fusion of synaptic vesicles with the plasma membrane (and subsequent neurotransmitter release)? a.) An increase in fusion events b.) a decrease in fusion events c.) no effect on fusion events

One of the characteristics of botulinum toxin (the cause of 'botulism') is a very specific protease activity, i.e., the toxin can cleave (cut), and thereby render nonfunctional, a SNARE protein associated with neurotransmitter-containing synaptic vesicles found in certain nerve terminals. Which of the following is the likely effect of this toxin on fusion of synaptic vesicles with the plasma membrane (and subsequent neurotransmitter release)? a.) An increase in fusion events b.) a decrease in fusion events c.) no effect on fusion events

Human Physiology: From Cells to Systems (MindTap Course List)

9th Edition

ISBN:9781285866932

Author:Lauralee Sherwood

Publisher:Lauralee Sherwood

Chapter4: Principles Of Neural And Hormonal Communication

Section: Chapter Questions

Problem 15RE

See similar textbooks

Similar questions

Name three features common to the activation of cytokine receptors and receptor tyrosine kinases. Name one difference with respect to the enzyme activity of these receptors.
A certain bacterium has a gene that encodes for a neurotoxin. This neurotoxin is highly specific for the synaptic end of the nerve, where it blocks the release of acetylcholine, a chemical necessary for transmission of nerve impulses across synapses. What is the chemical composition of this neurotoxin?
Clostridium tetani toxin blocks the exocytosis of GABA. A. What anatomical part of a pre-synaptic neuron would be affected by this? B. How would a post-synaptic neuron’s likelihood of experiencing an action potential be affected by this toxin? C. Explain, using at least TWO of the following terms: threshold, depolarization, repolarization, hyperpolarization, summation, IPSP, EPSP, exocytosis
In somewhat simple terms please explain the differences between electrical signal propagation through gap junctions and synapses. Which types of cells use each respective method, and how do these methods of transport differ?
A synaptic vesicle has a diameter of 40 nm. The concentration of a neurotransmitter inside this vesicle is 250 mM. How many molecules of this neurotransmitter are in the vesicle?
Name two elements of the cytoskeleton that are involved in the secretion of presynaptic button neurotransmitters, and indicate what role (function) this element has in the secretion process.
What ion is necessary for movement of the troponintropomyosin complex? What is the role of thesarcoplasmic reticulum in this process?
One of your classmates is planning to study endocytosis at neuronal synapses for their senior thesis. He is interested in what type of molecules neurons endocytose. They propose to use a cell line mutated in the microtubule motor kinesin to keep endocytic vesicles clustered at the synapse where they can be isolated into synaptosomes through differential centrifugation. The classmate shows you protocols for growing neurons in culture and one that demonstrates the feasibility of isolating synaptosomes. But you know there is something else wrong with this proposal that will keep it from succeeding. What is it?
Describe the 3 main steps for activation of receptor tyrosine kinases.
An effector neuron is a motor neuron that transmits impulses from the CNS to an effector (muscle or gland).In an experiment, it was determined that the effector neuron for muscle fibre 1 had a threshold level of –5 mV. The effector neuron for muscle fibre 2 had a threshold level of –16 mV. An electrical probe was used to stimulate these two effector neurons of the muscle fibres. Which of the following rows correctly identifies the reaction of each muscle fibre based on the applied stimulus voltage? Stimulus Voltage Muscle Fibre 1 Muscle Fibre 2 –20 mV Relaxed Contracted b. Stimulus Voltage Muscle Fibre 1 Muscle Fibre 2 –20 mV Contracted Relaxed c. Stimulus Voltage Muscle Fibre 1 Muscle Fibre 2 –10 mV Contracted Relaxed d. Stimulus Voltage Muscle Fibre 1 Muscle Fibre 2 –10 mV Relaxed Contracted
Which of the following statements best describes the features of voltage-gated K+ channels? They consist of 4 subunits, are activated at the same time as voltage-gated Na+ channels, but do not inactivate. They consist of 4 subunits, are activated by depolarisation and close slowly during the refractory period. They have 24 membrane spanning alpha helices, 4 of which have positively charged amino acids which promote a conformational change in the channel following depolarisation. They consist of 4 subunits and are open at rest which causes the resting membrane potential to be close to the K+ equilibrium potential.
. which of the following statements about heterotrimetric G proteins and their receptors is incorrect? A: when GTP binds to the alpha subunit of the G protein, the beta-gamma subunit dissociates from the alpha subunit B: G-protein coupled receptors contain nine transmembrane alpha helices C: binding of arrestin causes removal of the receptor from the membrane D: G protein- coupled receptors may be desensitized by serine phosphorylation I had chosen option A and got it wrong. What is the Correct answer and explain how it is. Also, where did i go wrong in choosing option A?