Chapter 10: Foundations of Genetics

A set of 66 flashcards focusing on key vocabulary and concepts from the chapter on the foundations of genetics.

Heredity

The passing of traits, genetic information, from parent to offspring.

Gregor Mendel

The father of heredity who studied garden peas.

Trait

A heritable feature.

Gene

The basic unit of inheritance.

Allele

A version of a gene.

Homozygous

Having two identical alleles for a particular gene.

Homozygous Dominant

Genotype composed of two dominant alleles (e.g., PP).

Homozygous Recessive

Genotype composed of two recessive alleles (e.g., pp).

Heterozygous

Genotype composed of one dominant and one recessive allele (e.g., Pp).

Locus

The location of a gene on a chromosome.

Punnett Square

A diagram that predicts the genotype of offspring from a particular cross.

Phenotype

The physical appearance of an individual.

Genotype

The genetic makeup of an individual.

P Generation

The parental generation in Mendel's experiments.

F1 Generation

The first filial generation, offspring of the P generation.

F2 Generation

The second filial generation, offspring of self-fertilization of the F1 generation.

Dominant Trait

A trait that appears in the phenotype when present in the genotype.

Recessive Trait

A trait that appears in the phenotype only when the dominant allele is not present.

Segregation

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

Independent Assortment

Mendel's second law stating that genes on different chromosomes are inherited independently.

Dihybrid Cross

A cross involving individuals heterozygous for two traits.

Polygenic Traits

Traits controlled by multiple genes.

Continuous Variation

Variation in traits that don't follow discrete categories.

Pleiotropic Effects

One allele affects multiple traits.

Incomplete Dominance

A situation where heterozygotes display an intermediate phenotype.

Codominance

Both alleles in a heterozygote are fully expressed.

Epistasis

The interaction between genes where one gene modifies the expression of another.

Epigenetics

Changes in phenotype without altering DNA sequence.

Chromosomal Theory of Inheritance

Principle stating that chromosomes are the hereditary material.

Sex-Linked Trait

A trait determined by a gene on a sex chromosome.

Linkage

The tendency of genes located close together to assort together.

Autosomes

Chromosomes that are identical in both males and females.

Nondisjunction

The failure of chromosomes to separate correctly during meiosis.

Aneuploidy

An abnormal number of chromosomes resulting from nondisjunction.

Pedigree

A family tree that traces the inheritance of traits.

Mutation

An accidental change in a DNA sequence.

Recessive Genetic Disorder

A disorder caused by mutant alleles that are recessive.

Sickle-cell Disease

A genetic disorder resulting in misshapen red blood cells.

Hemophilia

A sex-linked genetic disorder characterized by blood-clotting issues.

Tay-Sachs Disease

A genetic disorder that results in brain deterioration.

Huntington’s Disease

A dominant genetic disorder that causes brain cell deterioration.

Codominance Example

An example where both alleles express traits, like a horse with both black and white hairs.

Testcross

Crossing an individual with an unknown genotype with a homozygous recessive.

Nondisjunction Results

Conditions such as Down syndrome caused by incorrect chromosome separation.

Blood Types

The result of the combination of three alleles: A, B, i.

Phenotypic Expression

The observable traits of an organism influenced by genes.

Environmental Effects

Influences of the environment on gene expression.

Mendelian Inheritance

Inheritance patterns that follow Mendel's laws.

Chromosome Pairs

Humans have 23 pairs of chromosomes.

Sex Chromosomes

Chromosomes that determine an individual's sex (XX or XY).

Down Syndrome Symptoms

Includes delayed development and mental impairment.

Klinefelter Syndrome

A condition in males with an extra X chromosome.

Turner Syndrome

A condition in females where one X chromosome is missing.

Gametes

Reproductive cells that carry half the genetic information.

Mendels Traits

The dominant and recessive traits he observed in pea plants.

Mendel's Experiments

Studies primarily involving garden peas to establish foundational genetics.

Factors of Inheritance

Genetic information passed from parents to offspring.