Genetics: A Scientific Revolution

Vocabulary:

Gene: a segment of DNA which codes for a trait

Alleles: one of two versions of a gene Ex. Tall vs. short Brown eyes vs. blue eyes -Expressed with letters (WW, Ww, Bb)

Heredity: transmission of traits from parents to offspring Inheritance: genes acquired by offspring

Genotype: alleles that an organism inherits from its parents bb Bb Bb, BB

Phenotype: appearance of an organism as a result of genotype Genotype: bb Phenotype: blue eyes

Genetics: field of biology devoted to understanding the patterns/processes of inheritance

Gregor Mendel: Father of Genetics -born in Austria -entered a monastery at age 21 -studied peas -studied 15 traits over 28,000 generations -ridiculed for his findings

Pure Trait: traits that show up generation after generation

P – Generation (parental) – produce offspring with a mix of pure traits

F1 – Generation (filial) – offspring of the P-generation

F2- Generation – offspring of the F1 generation

Mendel’s 1st Experiment (Monohybrid Cross) P-Generation: Tall Flower X short flower F1 Generation: (All Tall) Tall X Tall F2 Generation: 75% Tall; 25% short

Principle of Dominance

Dominant Allele: the allele whose properties are expresses as phenotype

Recessive Allele: allele whose properties are not observed

Homozygous: when both alleles are alike (HH, hh, BB, bb, AA)

Heterozygous: alleles are not alike (Aa, Hh, Gg)

Law of Segregation: traits separate during gamete formation Diploid Cell Pp Tt pt Pt PT pT Haploid Cells

Punnett Square: displays the probability of genotypes/phenotypes P-generation T T Tt t t All Tall

F1 Generation – Tt X Tt