[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"detail-sidebar-cat-0-en-105":3,"doc-seo-595462-105":59,"doc-detail-595462-en":130},{"code":4,"msg":5,"data":6},0,"success",[7,13,18,23,28,33,38,43,48,51,55],{"id":8,"doc_module":4,"doc_module_name":9,"category_name":10,"show_sort_weight":11,"slug":12},1,"Document","Story & Novel",90,"story-novel",{"id":14,"doc_module":4,"doc_module_name":9,"category_name":15,"show_sort_weight":16,"slug":17},2,"Literature",80,"literature",{"id":19,"doc_module":4,"doc_module_name":9,"category_name":20,"show_sort_weight":21,"slug":22},4,"Exam",70,"exam",{"id":24,"doc_module":4,"doc_module_name":9,"category_name":25,"show_sort_weight":26,"slug":27},5,"Comic",60,"comic",{"id":29,"doc_module":4,"doc_module_name":9,"category_name":30,"show_sort_weight":31,"slug":32},6,"Technology",50,"technology",{"id":34,"doc_module":4,"doc_module_name":9,"category_name":35,"show_sort_weight":36,"slug":37},7,"Healthcare",40,"healthcare",{"id":39,"doc_module":4,"doc_module_name":9,"category_name":40,"show_sort_weight":41,"slug":42},8,"Research & Report",30,"research-report",{"id":44,"doc_module":4,"doc_module_name":9,"category_name":45,"show_sort_weight":46,"slug":47},9,"Religion & Spirituality",20,"religion-spirituality",{"id":46,"doc_module":4,"doc_module_name":9,"category_name":49,"show_sort_weight":46,"slug":50},"World Cup","world-cup",{"id":52,"doc_module":4,"doc_module_name":9,"category_name":53,"show_sort_weight":52,"slug":54},10,"Lifestyle","lifestyle",{"id":56,"doc_module":4,"doc_module_name":9,"category_name":57,"show_sort_weight":24,"slug":58},19,"General","general",{"code":4,"msg":60,"data":61},"ok",{"site_id":62,"language":63,"slug":64,"title":65,"keywords":66,"description":67,"schema_data":68,"social_meta":123,"head_meta":125,"extra_data":127,"updated_unix":129},105,"en","an-inexpensive-method-to-simulate-a-monohybrid-cross-using-wild-type-zebrafish-danio-rerio","An Inexpensive Method to Simulate a Monohybrid Cross Using Wild-Type Zebrafish (Danio rerio)","","Monohybrid crosses are implemented in an introductory biology laboratory using wild-type and non-pigmented zebrafish embryos to model a classic Mendelian 3:1 phenotypic ratio. 1-phenyl-2-thiourea (PTU) is used to suppress melanin synthesis, eliminating the need to maintain a separate albino fish line. Live embryos increase student engagement, while preserved embryos support reuse across multiple years without relying on day-specific embryo production. The approach also reduces requirements for extensive zebrafish facilities.",{"@graph":69,"@context":122},[70,84,105],{"@type":71,"itemListElement":72},"BreadcrumbList",[73,77,79,82],{"item":74,"name":75,"@type":76,"position":8},"https://docshare.wps.com","Home","ListItem",{"item":78,"name":9,"@type":76,"position":14},"https://docshare.wps.com/document/",{"item":80,"name":40,"@type":76,"position":81},"https://docshare.wps.com/document/research-report/",3,{"item":83,"name":65,"@type":76,"position":19},"https://docshare.wps.com/document/an-inexpensive-method-to-simulate-a-monohybrid-cross-using-wild-type-zebrafish-danio-rerio/595462/",{"url":83,"name":65,"@type":85,"image":86,"author":91,"headline":65,"publisher":94,"fileFormat":97,"inLanguage":63,"description":67,"dateModified":98,"datePublished":99,"encodingFormat":97,"isAccessibleForFree":100,"interactionStatistic":101},"DigitalDocument",{"url":87,"@type":88,"width":89,"height":90},"https://docshare.wps.com/thumbnails/an-inexpensive-method-to-simulate-a-monohybrid-cross-using-wild-type-zebrafish-danio-rerio/595462.png","ImageObject",300,407,{"name":92,"@type":93},"Well Done","Person",{"url":74,"name":95,"@type":96},"DocShare","Organization","application/pdf","2026-10-31","2026-10-15",true,{"@type":102,"interactionType":103,"userInteractionCount":19},"InteractionCounter",{"@type":104},"ViewAction",{"@type":106,"mainEntity":107},"FAQPage",[108,114,118],{"name":109,"@type":110,"acceptedAnswer":111},"Why does the lab use PTU in zebrafish embryos?","Question",{"text":112,"@type":113},"PTU blocks melanin synthesis, producing embryos that appear non-pigmented (albino-like) without maintaining a separate albino line.","Answer",{"name":115,"@type":110,"acceptedAnswer":116},"How does the method simulate a monohybrid cross?",{"text":117,"@type":113},"Embryos are distributed so that approximately 3:1 wild-type to non-pigmented specimens are obtained, mirroring the classic dominant-to-recessive phenotypic ratio.",{"name":119,"@type":110,"acceptedAnswer":120},"What are the key steps after embryo collection?",{"text":121,"@type":113},"Embryos are transferred to Petri dishes with Danieau solution, incubated with or without PTU at 7 hours post fertilization, then dead embryos are removed and surviving embryos are fixed and washed for sorting.","https://schema.org",{"og:url":83,"og:type":124,"og:title":65,"og:site_name":95,"og:description":67},"article",{"robots":126,"canonical":83},"index,follow",{"doc_id":128,"site_id":62},595462,1792768680,{"code":4,"msg":5,"data":131},{"doc_id":128,"user_id":132,"nickname":92,"user_avatar":133,"doc_module":4,"category_id":39,"category_name":40,"doc_title":65,"doc_description":67,"doc_content":134,"file_id":135,"file_url":136,"file_type":137,"file_size":138,"view_count":19,"is_deleted":4,"is_public":8,"is_downloadable":8,"audit_status":8,"page_count":29,"language":139,"language_code":63,"site_id":62,"html_lang":63,"table_of_contents":140,"faqs":141,"seo_title":142,"seo_description":67,"update_tm":143,"read_time":144,"preview_page_count":4},5909892210082,"https://ap-avatar.wpscdn.com/avatar/56001069da27c9f41e8?x-image-process=image/resize,m_fixed,w_180,h_180&k=1789614185077863061","An Inexpensive Method to Simulate a Monohybrid Cross Using Wild-Type Zebrafish (Danio rerio)  \nChristopher S. Lassiter  \nDepartment of Biology, Roanoke College, 221 College Lane, Salem, VA USA 24153  \nAbstract:Monohybrid crosses are taught in biology labs across the country using peas and corn. Students studying monohybrid crosses using zebrafish (Danio rerio) would encounter a new model organism, and those interested inhuman or veterinary medicine would have increased interest. To this end, our college has implemented a laboratory exercise at the introductory level using wild-type and non-pigmented zebrafish embryos to simulate a monohybrid cross. By using 1-phenyl-2-thiourea (PTU) to generate non-pigmented fish, the necessity of maintaining a separate albino line of fish is eliminated. Live embryos are preferable for generating student excitement; however, the option to use preserved embryos allows for re-use of fish over multiple years without relying on embryo production on a particular day.  \nKeywords: Mendel, zebrafish, monohybrid, genetics  \nIntroduction  \nIn the classroom, we are often challenged with presenting material in new and exciting ways. Monohybrid crosses in particular can be difficult to present in a novel way in an introductory college biology course for either majors or non-majors. Mendel famously used the pea, Pisum sativum, to discover the 3:1 phenotypic ratio of  \ndominant:recessive traits (Mendel, 1866) . Many high schools and colleges continue to use this model organism, as well as corn, to exemplify genetic crosses. In our introductory biology course serving a population of approximately 120 students per year, we have used corn to demonstrate both monohybrid and dihybrid crosses (Genetics of Corn Kit, Carolina Biological) .  \nStudents often have preconceived notions brought into the classroom and laboratory environment (Lazarowitz and Lieb, 2006) . While not the intent of educators, some students may receive the impression that monohybrid genetic crosses are the domain of plants after exploring the concept exclusively in corn. Those students with prior exposure to Punnett squares and Mendelian genetics would benefit from new examples. In addition, critical thinking skills can be developed in laboratory exercises through their inquiry-based nature (Howard and Miskowski, 2005) . Here I will describe a laboratory exercise involving a simulated monohybrid cross in zebrafish (Danio rerio) to complement common Mendelian laboratory exercises involving corn.  \nThis laboratory exercise emphasizes that the phenomenon of 3:1 phenotypic ratios can be found in animals as well as plants. In addition, the exercise  \nintroduces a common model organism to students. Finally, the exercise simulates albino zebrafish without the instructor having to maintain a line of albino fish. Therefore, the exercise is adapted for high schools and colleges having minimal zebrafish facilities and circumvents the need to maintain multiple genetic lines. While live embryos are the most advantageous for student interest, preserving the embryos ahead of the lab exercise allows for specimens to be used multiple years and without relying on embryo production on a particular day.  \nMaterials and Methods  \nWild-type zebrafish adults (Danio rerio) were purchased from Carolina Biological and housedin ten gallon tanks. Adults were kept on a 14h:10hday:night cycle at 28.5°C and fed a diet of Tetramin flakes and freeze-dried brine shrimp (Omega One) . Approximately 20 fish were bred over a collecting tray and embryos were collected 2 hours after simulated dawn. Embryos were transferred to 60 mm Petri dishes with 0.3x Danieau solution (Table 1) and kept at 28.5°C (Nasevicius and Ekker, 2000) .  \nAt 7 hours post fertilization (hpf), clutches of embryos were placed into either a new Petri dish of 0.3x Danieau or 0.3x Danieau containing 0.2 mM 1-phenyl-2-thiourea (PTU) . PTU blocks melanin synthesis resulting in embryos that appear albino (Karlsson e","cbCaio2ZMf2kC2YP","https://ap.wps.com/l/cbCaio2ZMf2kC2YP","pdf",440299,"English","# Introduction\n## Materials and Methods","[{\"question\":\"Why does the lab use PTU in zebrafish embryos?\",\"answer\":\"PTU blocks melanin synthesis, producing embryos that appear non-pigmented (albino-like) without maintaining a separate albino line.\"},{\"question\":\"How does the method simulate a monohybrid cross?\",\"answer\":\"Embryos are distributed so that approximately 3:1 wild-type to non-pigmented specimens are obtained, mirroring the classic dominant-to-recessive phenotypic ratio.\"},{\"question\":\"What are the key steps after embryo collection?\",\"answer\":\"Embryos are transferred to Petri dishes with Danieau solution, incubated with or without PTU at 7 hours post fertilization, then dead embryos are removed and surviving embryos are fixed and washed for sorting.\"}]","An Inexpensive Method to Simulate a Monohybrid Cross Using Wild-Type Zebrafish (Danio rerio) | PDF",1792081191,15]