Unit 6 review Bio

Blending Hypothesis

An outdated theory suggesting that offspring are a "blend" of the traits of their parents.

Particulate Hypothesis

Mendel’s theory that genes are inherited as discrete units (alleles) that do not blend.

Traits

Characteristics that are inherited, such as eye color or height.

Genetics

The study of heredity and the variation of inherited characteristics.

Purebred (True Breeding)

Organisms that produce offspring identical to the parent in a particular trait.

Cross

Mating of two organisms to observe inheritance patterns.

Cross Fertilization (Cross Pollination)

Fertilization between two different plants with different genetic traits.

Self-Fertilization (Self-Pollination)

When a plant fertilizes itself, typically with its own pollen.

Locus

The specific physical location of a gene on a chromosome.

Gene

A segment of DNA that encodes for a specific protein or trait.

Allele

Different forms of a gene, represented in genotype as letters.

Homozygous

An organism that has two identical alleles for a particular trait.

Heterozygous

An organism that has two different alleles for a particular trait.

Genome

The complete set of genes in an organism.

Genotype

The genetic makeup of an organism, specifically the alleles inherited.

Phenotype

The physical expression or appearance of a trait.

Dominant

An allele that expresses its effect even with one copy present in the genotype.

Recessive

An allele that expresses its effect only when two copies are present.

Punnett Square

A diagram used to predict the genetic outcomes of a cross.

Monohybrid Cross

A genetic cross involving one trait.

Testcross

A cross between an organism with an unknown genotype and a homozygous recessive individual.

Dihybrid Cross

A cross involving two traits.

Probability

The likelihood of a particular genetic outcome occurring.

Crossing Over

The exchange of genetic material between homologous chromosomes during meiosis.

Random Fertilization

The random combination of gametes during fertilization.

Independent Assortment

The principle that genes for different traits are inherited independently.

Genetic Linkage

Genes close together on the same chromosome are more likely to be inherited together.

Law of Segregation

Mendel's law stating that alleles separate during gamete formation.

Carrier

An individual who carries one copy of a recessive allele but does not express the disorder.

Sex-Linked Genes

Genes located on sex chromosomes, often expressed differently in males and females.

Autosomes

Chromosomes that are not sex chromosomes.

Sex Chromosomes

Chromosomes that determine the sex of an individual.

Incomplete Dominance

A form of inheritance where the heterozygous phenotype is a blend of the two homozygous phenotypes.

Codominance

A form of inheritance where both alleles are equally expressed in the heterozygous phenotype.

Polygenic Traits

Traits influenced by multiple genes, resulting in a continuous range of phenotypes.

Linkage Maps

Diagrams showing the relative positions of genes on a chromosome.

Pedigree

A family tree diagram used to track inheritance patterns of traits.

Karyotype

A photographic representation of an individual's chromosomes.

P, F1, & F2

Generations in Mendel's experiments: P (original) F1 (first offspring) F2 (second offspring).

Gregor Mendel

Father of genetics, conducted experiments with pea plants and formulated the Laws of Inheritance.

Thomas Hunt Morgan

Pioneering geneticist who discovered sex-linked inheritance and genetic linkage.

Reginald C. Punnett

Co-developed the Punnett square for predicting genetic outcomes.

Mendel’s Pea Plant Experiment

Experiment involving cross breeding pea plants to study inheritance patterns.

Genetic Variation

Variability in the genetic makeup of individuals within a population.

Inheritance Patterns

Different ways traits can be passed from parents to offspring.

Testcross

Used to determine the genotype of an individual with a dominant trait.