Term
Character (def)
Trait (def) |
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Definition
Character - Distinct heritable feature
Trait - character variants |
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Term
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Definition
| Plants that produce offspring of the same variety when they self-pollinate |
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Term
Hybridization (def)
P, F1 & F2 Generations (def) |
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Definition
Hybridization - Mating of two contrasting true-breeding varieties
P - True-breeding parents
F1 - hybrid offspring of the P generation
F2 - F1 individuals self-pollinate to produce the F2 generation |
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Term
| Mendel's 4 concepts to explain inheritance pattern |
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Definition
- Alleles, alternate version of genes account for inherited characters
- Each organism inherits two alleles of each character
- If two alleles at a locus differ, one is dominant, the other recessive; dominant is expressed, recessive has no effect
- Law of Segregation; the two alleles separate during gamete formation |
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Term
Homozygous (def)
Heterozygous (def) |
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Definition
Homo - two identical alleles for a character is homozygous for gene controlling that character
Hetero - Two different alleles for a gene, not true-breeding |
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Term
Phenotype (def)
Genotype (def) |
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Definition
Phenotype - physical appearance, expressed characteristics
Genotype - genetic makeup, assortment of alleles |
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Term
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Definition
Breeding an individual displaying a dominant trait with a homozygous recessive individual
If any offspring are homozygous recessive, the parent must be heterozygous |
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Term
| Law of Independent Assortment (def/proof) |
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Definition
- Each pair of alleles segregates independently of each other pair of alleles during gamete formation
- Technically only applies to alleles on
Proof - Dihybrid cross, 9:3:3:1 ratio only possible if the two traits are sorted individually |
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Term
| Deviation from Mendelian patterns, 3 situations |
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Definition
- Alleles not completely dominant or recessive
- When a gene has more than two alleles
- When a gene produces multiple phenotypes |
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Term
Complete Dominance (def)
Incomplete Dominance (def)
Codominance (def) |
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Definition
Complete - When phenotype of homozygous and heterozygous individuals is identical
Incomplete - Phenotype is somewhere between the phenotypes of the two parental varieties
Codominance - two dominant alleles affect the phenotype in separate, distinguishable ways |
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Term
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Definition
Single genes often have multiple phenotypic effects
Responsible for multiple symptoms of certain hereditary disease |
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Term
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Definition
| A gene at one locus alters the phenotypic expression of a gene at a second locus |
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Term
Quantitative characters (def)
Polygenic inheritance (def) |
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Definition
Quant - traits that vary in the population along a continuum
Polygenic - an additive effect of two or more genes on a single phenotype, indicated by a quantitative character (e.g. skin color) |
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Term
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Definition
The phenotypic range of a genotype influenced by the environment
e.g. Flowers with the same genotype can have different color depending on outside factors |
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Term
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Definition
| Characters that vary based on genetic and environmental factors |
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Term
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Definition
- Most common lethal genetic disease in US, 1:2500 people of European descent
- Defective or absent chloride transport channels in plasma membranes |
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Term
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Definition
- Affects 1:400 African-Americans
- Single amino acid in hemoglobin protein differs |
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