{"id":266110,"date":"2025-07-22T16:12:50","date_gmt":"2025-07-22T16:12:50","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=266110"},"modified":"2025-07-22T16:12:54","modified_gmt":"2025-07-22T16:12:54","slug":"so-a-color-blind-man-mates-with-a-heterozygous-woman","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/07\/22\/so-a-color-blind-man-mates-with-a-heterozygous-woman\/","title":{"rendered":"So, a color-blind man mates with a heterozygous woman."},"content":{"rendered":"\n

So, a color-blind man mates with a heterozygous woman. Using a Punnett square, determine the percentage of sons and daughters that will be color blind.<\/p>\n\n\n\n

The Correct Answer and Explanation is:<\/mark><\/strong>1<\/a><\/sup><\/p>\n\n\n\n\n\n

Let’s break this down using a Punnett square.<\/p>\n\n\n\n

Color blindness<\/strong> is an X-linked recessive trait, which means the gene responsible for color blindness is located on the X chromosome. Men have one X and one Y chromosome (XY), while women have two X chromosomes (XX). The color blindness allele is represented by “X^c” (for color blind) and the normal vision allele is “X^C” (for normal vision).<\/p>\n\n\n\n

Parents’ Genotypes:<\/h3>\n\n\n\n
    \n
  • Man<\/strong>: Since he is color blind, his genotype must be X^cY<\/strong>. He has only one X chromosome, which carries the color-blind allele.<\/li>\n\n\n\n
  • Woman<\/strong>: The woman is heterozygous, meaning she carries one normal X and one color-blind X. Her genotype is X^CX^c<\/strong>.<\/li>\n<\/ul>\n\n\n\n

    Punnett Square:<\/h3>\n\n\n\n

    We will use the genotypes of both parents to set up the Punnett square.<\/p>\n\n\n\n

    <\/th>X^C (Mom)<\/th>X^c (Mom)<\/th><\/tr><\/thead>
    X^c (Dad)<\/strong><\/td>X^cX^C (Daughter, Normal Vision)<\/td>X^cX^c (Daughter, Color Blind)<\/td><\/tr>
    Y (Dad)<\/strong><\/td>X^CY (Son, Normal Vision)<\/td>X^cY (Son, Color Blind)<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

    Analysis:<\/h3>\n\n\n\n
      \n
    • Daughters<\/strong>: From the Punnett square, we can see that daughters will inherit one X chromosome from each parent. If they inherit the X^C<\/strong> from their mother and the X^c<\/strong> from their father, they will have normal vision (X^CX^c). If they inherit the X^c<\/strong> from their mother and the X^c<\/strong> from their father, they will be color blind (X^cX^c). Thus, 50% of daughters will be color blind, and 50% will have normal vision.<\/li>\n\n\n\n
    • Sons<\/strong>: Sons will inherit the Y chromosome from their father and one X chromosome from their mother. If they inherit the X^C<\/strong>, they will have normal vision (X^CY). If they inherit the X^c<\/strong>, they will be color blind (X^cY). Thus, 50% of sons will be color blind, and 50% will have normal vision.<\/li>\n<\/ul>\n\n\n\n

      Conclusion:<\/h3>\n\n\n\n
        \n
      • 50%<\/strong> of daughters will be color blind.<\/li>\n\n\n\n
      • 50%<\/strong> of sons will be color blind.<\/li>\n<\/ul>\n\n\n\n

        This is a simple example of how X-linked recessive traits are inherited, with a male always passing his Y chromosome to his sons and one of his X chromosomes to his daughters.<\/p>\n\n\n\n

        \"\"<\/figure>\n","protected":false},"excerpt":{"rendered":"

        So, a color-blind man mates with a heterozygous woman. Using a Punnett square, determine the percentage of sons and daughters that will be color blind. The Correct Answer and Explanation is:1 Let’s break this down using a Punnett square. Color blindness is an X-linked recessive trait, which means the gene responsible for color blindness is […]<\/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-266110","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/266110","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=266110"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/266110\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=266110"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=266110"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=266110"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}