Mendel's Laws of Heredity

Flashcards on Mendel's Laws of Heredity, covering key terms, concepts, and genetic disorders like Huntington's Disease and Phenylketonuria.

Huntington's Disease (HD)

A hereditary disorder that begins with personality changes, forgetfulness, and involuntary movements, typically striking in middle adulthood and leading to complete loss of motor control and intellectual function over 15-20 years.

Pedigree

A family tree that uses specific symbols to represent family members and their relationships, often used to trace the inheritance of genetic traits or diseases.

Phenylketonuria (PKU)

A metabolic disorder caused by a disturbance in the metabolism of phenylalanine, leading to an excess of phenylpyruvic acid in the urine and, if untreated, mental retardation.

Gregor Mendel

A monk who studied inheritance in pea plants and developed the basic rules of heredity, including the law of segregation.

Genes

The basic units of heredity, now known as Mendel's 'elements,' which carry information for specific traits.

Alleles

Alternative forms of a gene that can cause variations in traits, such as wrinkled or smooth pea seeds, or Huntington's disease or PKU.

Genotype

An individual's combination of alleles for a particular gene, representing their genetic makeup.

Phenotype

The observed traits of an individual, resulting from the interaction of their genotype and the environment.

Mendel's First Law: Law of Segregation

Each individual has two 'elements' (alleles) for each trait, which separate during reproduction, with offspring receiving one allele from each parent. One allele can dominate the other.

Gametes

Sex cells (eggs and sperm) that carry just one allele for each gene.

Carriers

Individuals who have one copy of a recessive allele for a particular trait or disorder but do not express the trait themselves.

Mendel's Second Law: Law of Independent Assortment

Alleles for different genes assort independently of one another during gamete formation.

Loci

Specific locations of genes on chromosomes.

Linkage

The tendency of genes located close together on the same chromosome to be inherited together.

Recombination

A process during meiosis in which chromosomes exchange parts, leading to new combinations of alleles.

Linkage Analysis

Techniques that use information about violations of independent assortment to identify the chromosomal location of a gene.

Map Unit/Centimorgan

A unit of measurement for genetic distance, estimated by the number of recombinations per 100 gametes.

Hardy-Weinberg Equilibrium

The principle stating that allele and genotype frequencies in a population remain constant from generation to generation in the absence of other evolutionary influences.