Biosc&0150:&Foundations&of&Biology&I.& & Review&6:&&chapter&13& &!Adel,&Anthony,&Kathleen,&Megan,&Dr.&Swigonova& & Page&1&of&9&Review&chapter&13:&Mendel&&and&the&Gene&&1. What&is&the&difference&between&an&organism’s&genotype&and&phenotype?&The&genotype&of&an&organism&is&the&composition&of&alleles&in&its&genetic&material.&The&phenotype&is&the&physical&expression&of&allele s&bas ed &on&th e&pro tein s&encoded&by&the&genotype.&&2. Review&crosses&–&fill&in&the&table:&Monohybrid&Cross&A&cross&between&two&parents&that&carry&two&different&genetic&determinants&for&th e&same& trait.&&In&more&modern&terms,&a&cros s&between&two&parents&that&are&both&heterozygous&for&one&trait&Reciprocal&Cross&A& set& of& matings& where& you& switch& the& maternal& and& paternal& phenotypes&from&the&previous&mating&an d&pe rform &the &cros s.&Dihybrid&Cross&A&cross&between&two&individuals&who&are&both&heterozygous&for&two&trait&Test&cross&A&cross&between&an&individual&of&unknown&genotype&with&an&individual&who&is&h om o zyg ou s&reces sive &for&that&trait.&&Useful&for&determinin g&the&geno typ e&for&the&unknown&individ ual&&3. Vocabulary&review:&Dominant&allele&Allele& that& produces& the& dominant& phenotype& in& heterozygotes& and&homozygotes&Recessive&allele&Allele&that&produces&the&recessive&phenotypes&only&in&homozygous&recessive&individuals&Homozygous&Containing&two&of&the&same&alleles&for&a&trait&Heterozygous&Containing&two&different&alleles&for&a&trait&Hybrid&Offspring& from& a& cross& between& two& parents& homozygous& with& different&genotypes&&4. Introduction&to&Gen et ics&a. What& were& the& two& leading& hypotheses& for& the& pattern& of& inheritance?& Blending&Inheritance—traits & observed& are& a& blending& of& mother& and& father’s&traits.&Inheritance&of&acquired&characters—traits&observed&are&modified&traits&from &pa ren ts&b. What&is&a&model&organism?&Why&was&the&garden&pea&such&a&good&one?&A&species&that&is&used&for&research&because&it&is&practical&and&because&conclusions&drawn&from&studying&it&turn&out&to&apply&to&m an y&other&species&as&well.&The&garde n&pea&was&a&good&model&b eca us e&Mendel&could&control&which&parents&were&involved&in&ma ting&and&it&had&very&ea sy&categorical&traits&(color,&shape)&c. The&observable&trait&of&an&individual&is&known&as&its&_______________________&Phenotype&d. What&is&a& pure&line?&Consists&of& individuals&that& produce&offspring& identical&to& themselves&when&they&are&selfXpollinated&or&crosses&to&another&member&of&the&pureXline&population&e. What&are&Mendel’s&5&claims&(rules)?&i. Peas&have&two&alleles&ii. Alleles&do&not&blend&together&iii. Each&gamete&contains&one&allele&iv. Male&and&female&contribute&equally&to&genotype&of&offspring&v. Alleles&can&be&dominant&or&recessive&&Biosc&0150:&Foundations&of&Biology&I.& & Review&6:&&chapter&13& &!Adel,&Anthony,&Kathleen,&Megan,&Dr.&Swigonova& & Page&2&of&9&5. Single&Trait&Inheritance&&a. The& adults& used& in& an& initial& experimental& cross& are& the& ______________________.& Their&progeny&(offspring)&are&the&______________________.&Parental&generation;&F1&generation&b. True& or& False?& Individuals& with& the& dominant& phenotype& have& a& higher& fitness& than& do&individuals&with&th e&recessive&phenotype .&FALSE!&The&term&dominant&and&recessive&identify&only&which&phenotype&is&observed&in&individuals&carrying&two&different&alleles.&Example:&Huntington’s&disease&is&dominant&but&fatal.&&c. What&is&the&point&of&doing&a&reciprocal&cross?&A&reciprocal&cross&can&determine&whether&or&not&a&trait&is&sexXlinked&d. Different&versions&of&the&same&gene&are&known&as&_________________,&which&make&up&an&individual’s&_______ __ __ _ __ _ __ _.&Alleles;&genotype&e. What&is&the&principle&of&segregation?&Each&gamete&contains&one&allele&of&each&gene&(alleles&must&separate&into&different&gametes&during&meiosis)&f. If&the&allele&R&is&domina n t&to &r,&w ha t &are &th e&fo llo w in g&ge no ty p es?&vi. RR:&______________________________&Homozygous&dominant&vii. Rr:&_______________________________&Heterozygous&viii. rr:&________ __ __ _ __ _ __ __ _ __ _ __ __ _ __ &Homozygous&recessive&&&6. In&humans,& p igm e nt ed &eye&color&(brown)&is&dominant&to&unXpigmented&eye&color&(blue).&B&=&brown,&b&=&blue.&In&a&test&cross,&the&mother&had&blues&eyes&and&the&father&had&brown&eyes.&a. Fill& in& the& 2& possible& Punnett& Squares& (one& where& the& father& is& homozygous& dominant& for&brown&eyes,&and&the&other&where&he&is&heterozygous)&& & & &&&&&&&&b. If&the&father&was&homo zyg o us &do m in a n t&fo r&b rown&eyes,&ix. What&is&the&probability&of&having&a&child&with&brown&eyes?&1&x. What&is&the&probability&of&having&a&child&with&blue&eyes?&0&c. If&the&father&was&hete roz ygo u s&fo r&b ro w n&e yes ,&xi. What&is&the&probability&of&having&a&child&with&brown&eyes?&1/2&xii. What&is&the&probability&of&having&a&child&with&blue&eyes?&1/2&d. If&both&parents&had&blue &eye s,&xiii. What&is&the&probability&of&having&a&child&with&brown&eyes?&0&xiv. What&is&the&probably&of&having&a&child&with&blue&eyes?&1&e. If&both&parents&were&heterozygous&for&b rown&eyes,&xv. What&is&the&probability&of&having&a&child&with&brow n &eyes ?& 3/4&xvi. What&is&the&probably&of&having&a&child&with&blue&eyes?&1/4&f. If&the&mother&has&bro w n &eye s&a n d&a &ch ild &ha s &blu e&e yes ,&xvii. What&is&the&genotype&of&the&mother?&Bb&xviii. What&are&the&possible&genotypes&of&the&father?&Bb,&bb&xix. What&genotype&can&the&father&NOT&be?&BB&Bb&Bb&bb&bb&Bb&Bb&Bb&Bb&Biosc&0150:&Foundations&of&Biology&I.& & Review&6:&&chapter&13& &!Adel,&Anthony,&Kathleen,&Megan,&Dr.&Swigonova& & Page&3&of&9&7. Experiments&with&2&Traits:&The&Dihybrid&Cross&and&Testcross&a. What&is&the&definition&of&a&Dihybrid&cross?&A& mating& between&two& individuals& who& are& heterozygous& for&two&traits&(example& on& page&237)&b. What& were& the& two& possibilities& (assortment& type)& for&the&Dihybrid& cross& that& Mendel&hypothesized?& &Which&one&did&he&find&actually& occurred&experimentally?&&In& this&experiment&what&generations&did&he&need&to&mate&to&show&the&difference&between&the&two?&Independent&and&d ep en d ent&assortment;&independent;&two&F1&genera tion &me m be rs&c. What& were& the& phenotypic& ratio& results& of& the& cross& described& above& for& the& second&question&(page&237)?&&9:3:3:1&d. What&is&the&definition&of&a&test&cross?&&Why& is&this& useful&for&experimenters?&A&testcross&is&a&cross& b etween& two& parents,& one& that& co