Biology: A Guide to the Natural World with mybiology" (4th Edition)

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BIOL Study Guide Test 3 Chapter 11: Cross-pollinate – occurs when pollen is delivered to a flower from a different plant. Phenotypes – A physiological feature, bodily characteristic, or behavior of an organism. Genotype – An organism’s genetic makeup. First filial generation – The first generation son or daughter of a parent generation. Referred to as F 1 , second filial as F 2 ect. Allele – The proper name for an alternative form of a gene. (A “pure” yellow-seeded plant, having two yellow alleles, would be symbolized as YY. Meanwhile, pure green-seeded plants are yy, while mixed seeds are Yy.) Homozygous – An organism that has two identical alleles of a gene for a given character Heterozygous – An organism that has differing alleles for a character Dominant – A term used to designate an allele that is expressed in the heterozygous condition. In the heterozygous pea plant (Yy), the yellow allele (Y) is expressed, meaning it is dominant over the green allele (y). (smooth peas) Recessive – A term used to designate an allele that is not expressed in the heterozygous condition. The green allele (y) is recessive because it is not expressed when it exists heterozygously with the yellow allele (Y). Monohybrid Cross – When people breed organisms for a single difference such as looking to see how the offspring will come out. Dihybrid Cross – When you breed organisms for two characters Incomplete Dominance – A genetic condition in which neither allele is completely dominant, with the result that heterozygous genotypes can yield an intermediate phenotype. (Pink snap-dragons made from white and purple) Codominance – A condition in which two alleles of a given gene will have independent effects in a single organism. In such a situation, neither allele is dominant; rather, each is having a separate phenotypic effect. (AB Blood) Multiple Alleles – When three or more alleles exist in a population (such as human blood types) Polygenic Inheritance – The inheritance of a genetic character that is determined by the interaction of multiple genes, with each gene having a small additive effect on the character; The phenomenon of many genes having one effect (height, eye color, the length of an ear of corn, how much milk a cow will produce, ect.) Pleiotropy – The phenomenon of one gene having many effects. Bell Curve – A distribution of values that is symmetrical and largest around the average. Most biological traits manifest in this way. (The bell curve in height, tall and short being the minority) Gregor Mendel was the first person to comprehend some of the most basic principles of genetics. He worked in the mid-nineteenth century in what is now the Czech Republic.
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Bio Test 3 SG - BIOL Study Guide Test 3 Chapter 11...

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