{"id":134466,"date":"2024-09-01T16:42:56","date_gmt":"2024-09-01T16:42:56","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=134466"},"modified":"2024-09-01T16:42:58","modified_gmt":"2024-09-01T16:42:58","slug":"which-of-the-following-is-the-approximate-threshold-value-for-mammalian-neurons","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2024\/09\/01\/which-of-the-following-is-the-approximate-threshold-value-for-mammalian-neurons\/","title":{"rendered":"Which of the following is the approximate threshold value for mammalian neurons"},"content":{"rendered":"\n<p>Which of the following is the approximate threshold value for mammalian neurons?<\/p>\n\n\n\n<p>A.<br>+35 mV<\/p>\n\n\n\n<p>B.<br>-55 mV<\/p>\n\n\n\n<p>C.<br>0 mV<\/p>\n\n\n\n<p>D.<br>-80 mV<\/p>\n\n\n\n<p><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-6-color\">The Correct answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n<p>The approximate threshold value for mammalian neurons is <strong>B. -55 mV<\/strong>.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Explanation:<\/h3>\n\n\n\n<p>Neurons are specialized cells responsible for transmitting electrical signals throughout the nervous system. The generation and propagation of these electrical signals involve changes in the neuron&#8217;s membrane potential, which is the difference in electric potential between the inside and outside of the cell membrane.<\/p>\n\n\n\n<p>The membrane potential of a neuron at rest is typically around <strong>-70 mV<\/strong>, which is termed the <strong>resting membrane potential<\/strong>. This negative value is due to the differential distribution of ions across the cell membrane, primarily maintained by the sodium-potassium pump and the selective permeability of the membrane to different ions.<\/p>\n\n\n\n<p>To initiate an action potential, which is a rapid and transient change in membrane potential, the neuron must reach a specific critical level known as the <strong>threshold potential<\/strong>. This is the membrane potential at which voltage-gated sodium channels open, leading to a rapid influx of sodium ions into the cell and a consequent depolarization of the membrane.<\/p>\n\n\n\n<p>In mammalian neurons, the threshold potential is typically around <strong>-55 mV<\/strong>. This value is slightly less negative than the resting membrane potential of -70 mV. When the membrane potential reaches this threshold, it triggers the opening of additional sodium channels in a positive feedback loop, causing a rapid depolarization that constitutes the action potential.<\/p>\n\n\n\n<p>The other values listed in the options are not typically associated with the threshold potential for mammalian neurons:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>+35 mV<\/strong> represents the peak of the action potential, not the threshold.<\/li>\n\n\n\n<li><strong>0 mV<\/strong> is the point where the membrane potential is neither polarized nor depolarized and is not typically a threshold value.<\/li>\n\n\n\n<li><strong>-80 mV<\/strong> is below the resting membrane potential and not related to the threshold for action potential initiation.<\/li>\n<\/ul>\n\n\n\n<p>Thus, the correct answer is <strong>B. -55 mV<\/strong>, which aligns with the approximate threshold value needed to trigger an action potential in mammalian neurons.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Which of the following is the approximate threshold value for mammalian neurons? A.+35 mV B.-55 mV C.0 mV D.-80 mV The Correct answer and Explanation is: The approximate threshold value for mammalian neurons is B. -55 mV. Explanation: Neurons are specialized cells responsible for transmitting electrical signals throughout the nervous system. The generation and propagation [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[25],"tags":[],"class_list":["post-134466","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/134466","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/comments?post=134466"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/134466\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=134466"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=134466"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=134466"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}