Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Designer baby wikipedia , lookup
Genetically modified organism containment and escape wikipedia , lookup
Genetically modified crops wikipedia , lookup
Microevolution wikipedia , lookup
Transgenerational epigenetic inheritance wikipedia , lookup
History of genetic engineering wikipedia , lookup
Hardy–Weinberg principle wikipedia , lookup
Blending hypothesis • Originally, organisms were thought to be a blend of their parents’ characteristics. • Pure-breeds were defined as organisms that looked identical to their parents, and they looked like their parents, etc. • So now, using these two pieces of information, pretend you are a young scientist in the early 1800’s. You cross a purebred red flowering plant with a purebred white flowering plant. What do you expect to find? THE ACTUAL RESULTS… Mendelian Genetics Father of Modern Genetics • Austrian monk, high school teacher, and part-time garden keeper • First to propose biological inheritance of traits • Work not recognized until after his death • Knew nothing about DNA Why pea plants? • It’s what he had • Pea plants are true breeding • Gregor noticed that one stock of seed would produce only tall plants and another only short plants Cross-pollination P generation Next, Mendel wanted to find out if the recessive alleles had disappeared, orif were they still present in the F1 generation. VOCAB BREAK… • • • • • Traits Genes Alleles Genotype Phenotype Segregation • Mendel crossed the F1 generation with itself • He found that the recessive traits reappeared in some of the F2 generation • He proposed this was due to two things: the principle of dominance and segregation of alleles during formation of gametes Probability • Mendel categorized and counted the many offspring of each of his experiments. • He noticed that each time he repeated a particular cross he obtained similar results. For example: Every time he crossed two plants that were heterozygous for stem height (Tt), about ¾ of the offspring were tall and ¼ were short. Probability and Punnett Squares • Punnett squares are used to predict this probability • Monohybrid crosses can be performed to determine probability of genotype for one particular trait Genotypes AA Aa aa Homozygous Dominant Heterozygous Homozygous Recessive Law of Segregation • Mendel crossed the F1 generation with itself • He found that the recessive traits reappeared in some of the F2 generation • He proposed this was due to two things: the principle of dominance and segregation of alleles during formation of gametes Law of Independent Assortment • Genes that segregate independently do not influence each other’s inheritance