{"id":20100,"date":"2025-06-13T23:23:17","date_gmt":"2025-06-13T23:23:17","guid":{"rendered":"https:\/\/gaviki.com\/blog\/?p=20100"},"modified":"2025-06-13T23:23:25","modified_gmt":"2025-06-13T23:23:25","slug":"which-of-these-transmits-a-nerve-impulse-fastest","status":"publish","type":"post","link":"https:\/\/gaviki.com\/blog\/which-of-these-transmits-a-nerve-impulse-fastest\/","title":{"rendered":"Which of these transmits a nerve impulse fastest"},"content":{"rendered":"\n

Which of these transmits a nerve impulse fastest? A myelinated dendrite B myelinated axon C myelinated dendrite D unmyelinated dendrite<\/p>\n\n\n\n

The correct answer and explanation is:<\/strong><\/mark><\/p>\n\n\n\n

The correct answer is B: myelinated axon<\/strong>.<\/p>\n\n\n\n

\n\n\n\n

Explanation:<\/h3>\n\n\n\n

Nerve impulses (also called action potentials) travel along neurons to transmit signals. The speed at which these impulses travel depends on several factors, including:<\/p>\n\n\n\n

    \n
  1. Myelination<\/strong>: Whether the nerve fiber is covered by a myelin sheath.<\/li>\n\n\n\n
  2. Type of neuron fiber<\/strong>: Axon or dendrite.<\/li>\n\n\n\n
  3. Diameter<\/strong> of the fiber.<\/li>\n<\/ol>\n\n\n\n
    \n\n\n\n

    Myelination and Its Role:<\/h4>\n\n\n\n
      \n
    • Myelin<\/strong> is a fatty insulating layer formed by glial cells (Schwann cells in the peripheral nervous system and oligodendrocytes in the central nervous system).<\/li>\n\n\n\n
    • It wraps around the axon, creating segments separated by gaps called Nodes of Ranvier<\/strong>.<\/li>\n\n\n\n
    • Myelin increases impulse speed<\/strong> by allowing the nerve impulse to “jump” from one node to the next, a process called saltatory conduction<\/strong>.<\/li>\n\n\n\n
    • This jumping significantly speeds up transmission compared to continuous conduction along unmyelinated fibers.<\/li>\n<\/ul>\n\n\n\n
      \n\n\n\n

      Axons vs. Dendrites:<\/h4>\n\n\n\n
        \n
      • Axons<\/strong> are specialized for transmitting<\/strong> impulses away from the neuron\u2019s cell body toward other neurons or muscles.<\/li>\n\n\n\n
      • Dendrites<\/strong> mainly receive<\/strong> incoming signals and typically conduct impulses toward<\/strong> the cell body.<\/li>\n\n\n\n
      • Axons tend to be longer and more heavily myelinated<\/strong> than dendrites, making them optimized for rapid signal transmission.<\/li>\n\n\n\n
      • While some dendrites can be myelinated, they generally transmit signals more slowly because their primary role is receiving inputs rather than fast conduction.<\/li>\n<\/ul>\n\n\n\n
        \n\n\n\n

        Unmyelinated vs. Myelinated:<\/h4>\n\n\n\n
          \n
        • Unmyelinated fibers<\/strong> transmit impulses much more slowly because the signal travels continuously along the entire membrane.<\/li>\n\n\n\n
        • Unmyelinated dendrites are slowest due to lack of myelin and smaller diameter.<\/li>\n<\/ul>\n\n\n\n
          \n\n\n\n

          Why myelinated axon<\/strong> is fastest:<\/h3>\n\n\n\n
            \n
          • It combines the two factors that maximize conduction velocity: myelin insulation<\/strong> and axonal structure<\/strong> designed for rapid transmission.<\/li>\n\n\n\n
          • The myelin sheath enables saltatory conduction.<\/li>\n\n\n\n
          • The axon’s structure (diameter and protein channels) supports fast impulse propagation.<\/li>\n<\/ul>\n\n\n\n
            \n\n\n\n

            Summary Table:<\/h3>\n\n\n\n
            Fiber Type<\/th>Myelination<\/th>Impulse Speed<\/th><\/tr><\/thead>
            Myelinated Axon<\/td>Yes<\/td>Fastest<\/td><\/tr>
            Myelinated Dendrite<\/td>Yes<\/td>Slower than axon<\/td><\/tr>
            Unmyelinated Dendrite<\/td>No<\/td>Slowest<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

            Thus, myelinated axons transmit nerve impulses the fastest.<\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"

            Which of these transmits a nerve impulse fastest? A myelinated dendrite B myelinated axon C myelinated dendrite D unmyelinated dendrite The correct answer and explanation is: The correct answer is B: myelinated axon. Explanation: Nerve impulses (also called action potentials) travel along neurons to transmit signals. The speed at which these impulses travel depends on […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-20100","post","type-post","status-publish","format-standard","hentry","category-quiz-questions"],"_links":{"self":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/20100","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/comments?post=20100"}],"version-history":[{"count":1,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/20100\/revisions"}],"predecessor-version":[{"id":20101,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/20100\/revisions\/20101"}],"wp:attachment":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/media?parent=20100"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/categories?post=20100"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/tags?post=20100"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}