patterns

• Genetics is the study of heredity.
• Genes are a set of characteristics inherited from your parents and are found on chromosomes, containing DNA.
• True-breeding plants, such as those used by Mendel in his experiments, are self-pollinating plants that produce offspring identical to themselves.
• Cross-pollination is the process of pollinating plants with different characteristics.
• Mendel studied 7 different pea plant traits.
• A trait is a specific characteristic, such as color.
• Mendel’s traits were contrasting, with the original pair of plants being referred to as “parent”, or P, and the offspring as F1.
• F1 hybrid plants are those with the trait of only one of the parents.
• Inheritance is determined by chemical factors that determine traits and are passed from one generation to the next, these chemical factors are called genes.
• Each of the traits was controlled by one gene that occurred in contrasting forms, these different forms are called alleles.
• The principle of dominance states that some alleles are dominant while others are recessive, with a dominant allele always expressed unless there are two recessive alleles.
• In peas, tall is dominant while short is recessive; yellow dominant, green recessive.
• Mendel’s conclusions include the reappearance of recessive traits in approximately one-fourth of F2 plants, due to a segregation, or separation, of alleles during the formation of the sex cells (gametes).
• Two alleles will segregate from each other so that each gamete carries only a single copy of each gene, resulting in each F1 plant producing two types of gametes - those with a dominant allele and those with a recessive.
• Alfred Sturtevant hypothesized that the farther the two genes were, the more likely they are to be separated in crossing-over in meiosis
• Sturtevant hypothesized that the farther apart the two genes were, the more likely they were to be separated by crossing-over during meiosis.
• a gene map is a map of location of each genes
• Crossing-over events exchange and separate linked genes to produce new combinations, this is where genetic diversity comes from.
• Rabbit fur color is controlled by four alleles (C, c, ch, ch), resulting in a large range of variation.
• Thomas Morgan discovered that it is the chromosomes that assort independently, not the individual genes.
• characteristics are not only determined by genes, but also in genes and the environment.
• Alfred Sturtevant discovered the gene map
• Thomas Morgan discovered that each chromosome is a group of linked genes.
• Codominance is when both alleles contribute to the phenotype.
• Thomas Morgan led to 2 conclusions: a chromosome is a group of linked genes, and it is the chromosome that assorts independently, not the individual genes
• Probability is the likelihood that an event will occur, and scientists use probability to predict the outcomes of genetic crosses.
• Probability can be used to predict the outcome of a large number of events, but it cannot predict the exact outcome of a single event.
• the first summary of Mendel's principle is genes determine the inheritance of biological characteristics.
• Independent Assortment is the law that states genes for different traits can segregate independently during the formation of gametes.
• Homozygous refers to two identical alleles (TT or tt )
• Each adult has two copies of the gene, one from each parent, which segregate when gametes are formed.
• Heterozygous refers to two different alleles (Tt)
• Test cross is a method used by Mendel to test organisms with an unknown genotype.
• Genotype refers to the genetic makeup, such as TT, Tt or tt.
• Phenotype refers to the physical characteristic, such as Tall, short.
• the second summary of Mendel's principle is cases where two or more alleles of the gene exist, some alleles are dominant and some are recessive.
• Incomplete Dominance is a case in which one allele is not completely dominant over another.
• the fourth principle summary of Mendel's principle is alleles for different genes usually segregate independently from one another.
• Punnett Squares are used to represent the possible gene combinations that result from a genetic cross.
• true breeding plants were the basis of mendel's experiements