Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Working Genetics Problems
Document related concepts
Polycomb Group Proteins and Cancer wikipedia , lookup
Site-specific recombinase technology wikipedia , lookup
Public health genomics wikipedia , lookup
Genome evolution wikipedia , lookup
History of genetic engineering wikipedia , lookup
Nutriepigenomics wikipedia , lookup
Ridge (biology) wikipedia , lookup
Gene expression programming wikipedia , lookup
Genomic imprinting wikipedia , lookup
Minimal genome wikipedia , lookup
Artificial gene synthesis wikipedia , lookup
Dominance (genetics) wikipedia , lookup
Epigenetics of human development wikipedia , lookup
Genome (book) wikipedia , lookup
Biology and consumer behaviour wikipedia , lookup
Gene expression profiling wikipedia , lookup
Quantitative trait locus wikipedia , lookup
Transcript
Working Genetics Problems solving problems with Punnett squares © 2006 Plano ISD, Plano, TX Always follow these 3 steps when working genetics problems. © 2006 Plano ISD, Plano, TX 1 Write the key. Information needed to write the key will either be stated in the problem or given. 2 Determine the genotypes of both parents. 3 Solve the problem using a Punnett square. © 2006 Plano ISD, Plano, TX Possible Each reproductive cell contributes combinations of half of theare genes parent’s shown in genes a Punnett to its square. offspring. Each parent Purple Both White One parent color is dominant parents flower contributes color a a purple over contribute is purple recessive white. flower a flower white to gene; purple; one gene. flower therefore, parent gene. the contributes a offspring white flower is white. gene. © 2006 Plano ISD, Plano, TX Possible Each reproductive cell contributes combinations of half ofare genes its shown genes to aitsPunnett in offspring. square. Yellow seed color is dominant over green. © 2006 Plano ISD, Plano, TX Substitute letters for genes. Purple flower color is dominant over white. P- purple p - white © 2006 Plano ISD, Plano, TX P p PP Pp Pp pp P p Substitute letters for genes. Yellow seed color is dominant over green. Y - yellow y - green © 2006 Plano ISD, Plano, TX Y Y y Yy Yy y Yy Yy How are these flowers different? PP Pp Both flowers have the same physical appearance or phenotype: they are both purple. The flowers have different genetic makeup or genotype. © 2006 Plano ISD, Plano, TX Describe the phenotype of these peas. © 2006 Plano ISD, Plano, TX A purple flower can be pure (homozygous) PP or hybrid (heterozygous). Pp The phenotype is the same: both flowers are purple. The genotype is different: one flower is PP, one is Pp. © 2006 Plano ISD, Plano, TX A white flower can be only be pure (homozygous). Why? © 2006 Plano ISD, Plano, TX pp Follow these steps for every genetics problem. 1. Write the key. 1 upper case = dominant trait P = purple lower case = recessive trait p = white 2. Determine both genotypes (parents). 2 Cross a pure purple flower with a white flower. PP x pp 3. Work the problem with Punnett square. 3 © 2006 Plano ISD, Plano, TX
