Genetics and Molecular Biology: From Traits to Genetic Information

Vocabulary practice flashcards covering fundamental genetics concepts, including phenotype, genotype, gene, allele, locus, genome structure, and foundational experiments from Chapter 1.

Phenotype

The observable, measurable, or classifiable manifestation of a trait evaluated by defined criteria, including physical, physiological, or biochemical characteristics.

Genotype

The specific combination of alleles possessed by an individual at a designated locus or set of loci, distinct from the entire genome.

Gene

A defined unit of hereditary information or biological function within genetic material that can produce a functional RNA or protein product.

Allele

One of the alternative sequence variants or forms of a specific gene residing at the same locus on a chromosome.

Locus

The defined physical position or genomic coordinate of a gene or specific sequence on a chromosome or reference genome.

DNA

A nucleic acid molecule that stores and carries hereditary information across cellular contexts, comprising both genic and non-genic regions.

RNA

A versatile class of nucleic acids functioning as informational intermediates, catalytic elements, structural components, or regulatory molecules beyond merely being temporary DNA copies.

Genome

The complete set of genetic material belonging to an organism, cell, or organelle, encompassing protein-coding genes, RNA genes, and all non-coding sequences.

Chromosome

A cellular structure composed of organized DNA and associated molecules that carries genetic material, accommodating multiple genes, loci, and non-coding sequences.

Homologous Chromosomes

A pair of corresponding chromosomes containing matching loci in equivalent positions, which may carry identical or different alleles.

Organellar Genome

The entire independent complement of genetic material residing within a specific cellular organelle, such as a mitochondrion or chloroplast.

Non-coding DNA Sequences

Components of the genome that do not code for proteins, often functioning in regulation or chromosome structure, or possessing unknown biological roles.

Functional RNA

An RNA molecule that acts as the final functional product of a gene to perform regulatory, catalytic, or structural roles without undergoing translation into protein.

HBB Gene

The gene encoding the $\beta$-globin protein subunit, used as a model connecting sequence variants (alleles) to molecular products, cellular phenotypes, and organismal traits.

ABO Blood Group Model

A classical multi-allele genetic system used to demonstrate distinct hierarchical levels: the ABO gene, specific alleles ($I^A$, $I^B$, $i$), diploid genotypes, and observable blood-type phenotypes.

Mendelian Cross Analysis

The methodology of using controlled breeding crosses and quantitative offspring ratios to deduce discrete units and transmission laws of inheritance prior to knowing their molecular structure.

Chromosome Theory of Linkage (Morgan)

The historical expansion linking abstract hereditary units to physical chromosomes, demonstrating genetic linkage and relative linear gene positioning on chromosomes.

Phenotypic Variation

The total observed variation in a trait across individuals, arising from genetic differences, environmental influences, developmental timing, and technical measurement error.

Genome Size Discrepancy

The phenomenon where genome size does not directly correlate with total gene count, primarily caused by differences in repetitive DNA, introns, and non-coding regions.

Gene-Phenotype Association vs. Causality

The distinction where statistical correlation between an allele and a trait indicates association, but establishing direct causality requires mechanistic and functional validation.