BIO102

• Genetics is a branch of biology which deals with heredity and variation.
• A character is a heritable feature that varies among individuals.
• A trait is a variant for a character.
• A gene is a “heritable factor” and the basic unit of heredity.
• An allele represents different variations in our genes and different versions of a gene.
• Homozygous refers to identical/same (pair of) alleles for a gene.
• Heterozygous refers to different alleles.
• Progeny refers to offspring.
• The Blending Hypothesis is an idea that genetic materials from both parents will blend together.
• The Particulate Hypothesis is an idea that parents pass on discrete heritable units (genes) to their offspring.
• Charles Darwin’s Blood Theory of Heredity suggests that traits of the parents were passed to their offspring by blood.
• Gregor Johann Mendel, the Father of (modern) Genetics, discovered the basic principles of heredity by breeding garden peas.
• Mendel’s experiment on pea plants concluded that the yellow-colored trait was the dominant one and the green trait was recessive/hidden.
• Mendel’s experiment also concluded that when a purebred yellow-seeded plant was crossed with a purebred green-seeded plant, all the offspring were yellow-seeded.
• Mendel then let the yellow-seeded hybrid plants self-fertilize and the second breeding produced both yellow and green seeded plants.
• The phenotypic percentage for a monohybrid cross is 100% blue flower.
• The genotypic ratio for a monohybrid cross is 4 heterozygous (Bb) / (4:0).
• The genotypic percentage for a monohybrid cross is 100% heterozygous (Bb).
• The genotypic ratio for a dihybrid cross is 4 heterozygous (RrYy) / (4:0).
• The genotypic percentage for a dihybrid cross is 100% heterozygous (RrYy).
• The phenotypic ratio for a dihybrid cross is 4 red flowers / (4:0).
• The phenotypic ratio for a monohybrid cross is 4 blue flowers / (4:0).
• The parental genotype for a monohybrid cross is represented as BB x bb.
• The FOIL method is a method used to segregate the alleles of each parent; used to derive the parental gametes from the parental genotypes.
• The phenotypic percentage for a dihybrid cross is 100% red flower.
• Mendelian genetics is a guide to Punnett Squares.
• The parental genotype for a dihybrid cross is represented as RrYy x RrYy.
• Mendel used pea plants for his experiment due to their short generation time and large number of offspring.
• A dihybrid cross is a cross between parents that differ in two contrasting traits.
• A monohybrid cross is a cross between parents that differ in one contrasting trait.
• Mating in pea plants could be controlled (self-pollination/cross-pollination).
• Hybridization is the mating of two contrasting true-breeding varieties.
• Genes are unit factors that control the traits, while alleles are alternative forms of a single gene.
• Mendel’s Model explains the 3:1 inheritance pattern observed among the F2 offspring.
• Each gene resides at a locus on a chromosome, and each individual receives one (allele) from each parent.
• The second filial generation (F2 Generation) is the offspring of the F1 Generation.
• The first filial generation (F1 Generation) is the offspring of parents.
• Testcross is the breeding of an organism of unknown genotype with a recessive homozygote, which can reveal the genotype of the said organism.
• Punnett Square is a diagram devised by Reginald C. Punnett that shows possible combinations of alleles (possible genotypes and phenotypes) of the offspring.
• The Principle of Paired Unit Factors states that traits are controlled by unit factors which exist in pairs in individual organisms.