{"id":266142,"date":"2025-07-22T16:24:55","date_gmt":"2025-07-22T16:24:55","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=266142"},"modified":"2025-07-22T16:24:57","modified_gmt":"2025-07-22T16:24:57","slug":"sex-linked-crosses-complete-punnett-squares-to-answer-the-question-below","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/07\/22\/sex-linked-crosses-complete-punnett-squares-to-answer-the-question-below\/","title":{"rendered":"Sex-linked Crosses &#8211; Complete punnett squares to answer the question below."},"content":{"rendered":"\n<p>Sex-linked Crosses &#8211; Complete punnett squares to answer the question below. 1. Red-green colorblindness is a recessive allele carried on the X chromosome. A colorblind male mates with a non-colorblind heterozygous female. What are the expected ratios for genotype and phenotype of the offspring? Genotypic Ratios Phenotypic Ratios<\/p>\n\n\n\n<p><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-1-color\">The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n<p>To solve this, let&#8217;s break it down step by step and use a Punnett square to find the genotypic and phenotypic ratios.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Given:<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Red-green colorblindness is <strong>recessive<\/strong> and located on the <strong>X chromosome<\/strong>.<\/li>\n\n\n\n<li>A <strong>colorblind male<\/strong> has the genotype <strong>X\u1d9cY<\/strong>, where <strong>X\u1d9c<\/strong> is the X chromosome with the colorblind allele and <strong>Y<\/strong> is the Y chromosome.<\/li>\n\n\n\n<li>A <strong>heterozygous female<\/strong> has the genotype <strong>X\u1d9cX<\/strong>, where <strong>X\u1d9c<\/strong> carries the colorblind allele and <strong>X<\/strong> carries the normal vision allele.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Cross:<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Male: <strong>X\u1d9cY<\/strong><\/li>\n\n\n\n<li>Female: <strong>X\u1d9cX<\/strong><\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Punnett Square:<\/h3>\n\n\n\n<p>The offspring will inherit one X chromosome from the mother and either an X or a Y chromosome from the father.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th><strong>Mother\\Father<\/strong><\/th><th><strong>X\u1d9c<\/strong><\/th><th><strong>Y<\/strong><\/th><\/tr><\/thead><tbody><tr><td><strong>X\u1d9c<\/strong><\/td><td>X\u1d9cX\u1d9c<\/td><td>X\u1d9cY<\/td><\/tr><tr><td><strong>X<\/strong><\/td><td>X\u1d9cX<\/td><td>XY<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h3 class=\"wp-block-heading\">Genotypic Ratios:<\/h3>\n\n\n\n<p>From the Punnett square, we get the following genotypes for the offspring:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>X\u1d9cX\u1d9c<\/strong> (Colorblind female): 1<\/li>\n\n\n\n<li><strong>X\u1d9cX<\/strong> (Normal vision female but a carrier): 1<\/li>\n\n\n\n<li><strong>X\u1d9cY<\/strong> (Colorblind male): 1<\/li>\n\n\n\n<li><strong>XY<\/strong> (Normal vision male): 1<\/li>\n<\/ul>\n\n\n\n<p><strong>Genotypic Ratio<\/strong>: 1 X\u1d9cX\u1d9c : 1 X\u1d9cX : 1 X\u1d9cY : 1 XY<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Phenotypic Ratios:<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Colorblind females (X\u1d9cX\u1d9c)<\/strong> and <strong>colorblind males (X\u1d9cY)<\/strong> will exhibit colorblindness.<\/li>\n\n\n\n<li><strong>Normal vision females (X\u1d9cX)<\/strong> and <strong>normal vision males (XY)<\/strong> will not be colorblind.<\/li>\n<\/ul>\n\n\n\n<p>So, the phenotypic ratio will be:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Colorblind offspring<\/strong>: 2 (1 X\u1d9cX\u1d9c female + 1 X\u1d9cY male)<\/li>\n\n\n\n<li><strong>Normal vision offspring<\/strong>: 2 (1 X\u1d9cX female + 1 XY male)<\/li>\n<\/ul>\n\n\n\n<p><strong>Phenotypic Ratio<\/strong>: 2 colorblind : 2 normal vision<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Conclusion:<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Genotypic Ratio<\/strong>: 1 X\u1d9cX\u1d9c : 1 X\u1d9cX : 1 X\u1d9cY : 1 XY<\/li>\n\n\n\n<li><strong>Phenotypic Ratio<\/strong>: 2 colorblind : 2 normal vision<\/li>\n<\/ul>\n\n\n\n<p>This cross demonstrates how X-linked recessive traits are inherited differently in males and females, as males only have one X chromosome and thus will express any X-linked recessive trait.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"https:\/\/learnexams.com\/blog\/wp-content\/uploads\/2025\/07\/learnexams-banner6-1545.jpeg\" alt=\"\" class=\"wp-image-266145\"\/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Sex-linked Crosses &#8211; Complete punnett squares to answer the question below. 1. Red-green colorblindness is a recessive allele carried on the X chromosome. A colorblind male mates with a non-colorblind heterozygous female. What are the expected ratios for genotype and phenotype of the offspring? Genotypic Ratios Phenotypic Ratios The Correct Answer and Explanation is: To [&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-266142","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/266142","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=266142"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/266142\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=266142"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=266142"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=266142"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}