genetics quiz tuesday

• homozygous: two same alleles
• heterozygous: one dominant, one recessive
• purebred/true-breeding: a plant or animal that has been bred from parents that are of the same breed
• hybrid: the offspring of two plants or animals of different species or varieties, such as a mule (a hybrid of a donkey and a horse)
• wild type: the original version of a gene that is not altered by mutation or selection, homozygous
• p generation: the original (parent) generation of a species that produces offspring of the same species
• f1 generation: offspring of the first generation that are produced by a cross between the parents
• trait: a distinguishing quality or characteristic, typically one belonging to a person
• heredity: the passing on of physical or mental characteristics genetically from one generation to another
• genetics: the study of heredity and the variation of inherited characteristics.
• probability: the likelihood of an event happening, calculated by dividing the number of times an event occurs by the total number of times it can happen
• phenotype: the physical aspect of a trait that is expressed by an organism
• genotype: the genetic makeup of an individual organism.
• pollination: the transfer of pollen to a stigma, ovule, flower, or plant to allow fertilization
• cross pollination is when pollen from one flower is transferred to another flower of the same species
• self pollination is when pollen is transferred from the anther to the stigma of the same flower
• mendel's experiments: he used garden peas to study inheritance
• law of dominance: there are two alleles from each parents, dominant alleles mask recessive alleles
• law of segregation: during gamete formation, alleles separate into different cells so that each cell receives only one copy of each gene, resulting in allele pairs
• law of independent assortment: alleles are randomly segregated during meiosis
• how the law of dominance is shown in meiosis: anaphase I/II (homologous pairs/chromosomes are pulled apart)
• how the law of segregation is shown in meiosis: anaphase I/II (homologous pairs/chromosomes split apart)
• how the law of independent assortment is shown in meiosis: prophase I/metaphase I/II (crossing over/randomly lining up in the middle)
• multiplication rule: multiply two probabilities (trait 1 and trait 2)
• addition rule: add two probabilities (trait 1 or trait 2)
• incomplete dominance: dominant phenotype is intermediate between the recessive phenotypes
• codominant inheritance: both alleles contribute to the expression of the phenotype, neither one being completely masked by the other
• multiple alleles: more than two alleles for a gene
• epistasis: one trait depends on the other to be expressed
• sex-linked genes: sex chromosomes have traits that are unrelated to gender (located in x-chromosomes)
• how statistics can be applied to genetics: genetic mapping, probability using Punnett squares and chi-squared
• chi-squared formula: Σ (o-e)^2/e
• polygenic trait: a trait that is controlled by multiple genes
• complex characters: traits affected by the environment and genes
• how the environment can change/influence the expression of genetic traits: light intensity, temperature, humidity, pH, and nutrients
• pleiotropy: the production by a single gene of two or more unrelated phenotypic effects.
• sex-influenced trait: a trait that is more common in one sex than the other (males and females express different traits)
• SRY gene: A gene that determines the sex of an organism by producing the sex hormone testosterone (y chromosome)
• the importance of SRY gene in male development: needed for testosterone and the production of sperm
• gene linkage: the tendency for genes to be located close to each other on a chromosome, causes the genes to be inherited togehter