Answer Happy

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question 1) Which of the following is true regarding the pre-ganglionic and post-ganglionic neurons of the PSNS? 1) A) Both neurons release neurotransmitter from varicosities B) Both neurons release Ach to signal their target cells C) Both neurons originate (have their cell body) in the CNS D) One neuron releases Ach to signal target cells and the other neuron releases norepinephrine

4) 4) Which of the following is the best explanation for why cardiac contractile fibers depolarize and contract in a defined pathway, ensuring the complete contraction cycle of the heart? A) The gap junctions at the intercalated discs allow for ion flow to conduct current from one fiber to the next in a defined pathway B) The SA node delivers the contraction signal to the right atrium, then the left atrium, and then the AV node delivers the contraction signal to the right ventricle and then the left ventricle. C) The flow of blood into each chamber causes first a stretch of the fibers, followed by a reflexive contraction of the fibers, ensuring that the heart continues to contract in the absence of current D) The contraction signal produced by the SNS targets every fiber in a specific sequenca