Which of the following correctly describes an erection?<\/p>\n\n\n\n
Group of answer choices<\/p>\n\n\n\n
Smooth muscles of vascular spaces in the penis contract.
Parasympathetic impulses constrict arteries leading to the penis.
Parasympathetic neurons release nitric oxide causing dilation of small arteries in the penis.
The spongy tissue in the penis fills with air.<\/p>\n\n\n\n
The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n Correct Answer:<\/strong> Explanation:<\/strong><\/p>\n\n\n\n An erection is a physiological response primarily controlled by the parasympathetic division of the autonomic nervous system<\/strong>, and it involves complex interactions between the nervous and vascular systems.<\/p>\n\n\n\n During sexual arousal, parasympathetic nerve fibers<\/strong> originating from the sacral spinal cord (S2\u2013S4) are activated. These fibers release nitric oxide (NO)<\/strong>, a key neurotransmitter and vasodilator. Nitric oxide stimulates the production of cyclic guanosine monophosphate (cGMP)<\/strong> within the smooth muscle cells of the corpora cavernosa<\/strong>, which are the two columns of erectile tissue in the penis.<\/p>\n\n\n\n As cGMP levels increase, the smooth muscle of the arteries and arterioles supplying the penis relaxes<\/strong>, causing vasodilation<\/strong>. This relaxation allows a significantly increased volume of blood to flow into the penile tissues. The blood fills the vascular spaces<\/strong> in the corpora cavernosa, causing the tissue to expand<\/strong> and become firm.<\/p>\n\n\n\n At the same time, the outflow of blood is restricted<\/strong> because the expanding erectile tissues compress the veins that normally drain blood from the penis. This process helps maintain the erection by trapping blood within the erectile tissue<\/strong>.<\/p>\n\n\n\n Let\u2019s analyze why the other answer choices are incorrect:<\/p>\n\n\n\n In summary, nitric oxide released from parasympathetic neurons initiates the vasodilation<\/strong> necessary for penile erection, making it the correct and scientifically accurate answer.<\/p>\n","protected":false},"excerpt":{"rendered":" Which of the following correctly describes an erection? Group of answer choices Smooth muscles of vascular spaces in the penis contract.Parasympathetic impulses constrict arteries leading to the penis.Parasympathetic neurons release nitric oxide causing dilation of small arteries in the penis.The spongy tissue in the penis fills with air. The Correct Answer and Explanation is: Correct […]<\/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-217004","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/217004","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=217004"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/217004\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=217004"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=217004"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=217004"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
Parasympathetic neurons release nitric oxide causing dilation of small arteries in the penis.<\/strong><\/p>\n\n\n\n
\n\n\n\n\n
This is incorrect because an erection involves relaxation<\/strong>, not contraction, of smooth muscle to allow blood inflow.<\/li>\n\n\n\n
This is the opposite of what actually occurs. Parasympathetic impulses cause dilation<\/strong>, not constriction.<\/li>\n\n\n\n
This is completely incorrect. The erectile tissue fills with blood<\/strong>, not air.<\/li>\n<\/ul>\n\n\n\n