DNA Mutation and Speciation Vocabulary

Vocabulary flashcards covering key mutation concepts (point, deletion, frameshift) and core speciation ideas (species concepts, gene pool isolation, allopatric speciation, subspecies, hybrids, and prezygotic barriers) as discussed in the lecture notes.

Point mutation

A mutation that changes a single nucleotide in DNA, which can alter a codon and potentially the amino acid sequence of the resulting protein.

Deletion mutation

The loss of one or more nucleotides from DNA, which can shift the reading frame and alter downstream amino acids.

Frameshift mutation

A mutation caused by insertions or deletions that shift the reading frame of codons in mRNA, typically changing many downstream amino acids.

Messenger RNA (mRNA)

The RNA copy transcribed from DNA that carries genetic information from the nucleus to ribosomes for protein synthesis.

Speciation

The evolutionary process by which one population splits into two or more distinct species.

Biological species concept

A species is a group of interbreeding natural populations that are reproductively isolated from other such groups.

Morphological (morphological) species concept

Species are defined by observable physical traits; practical but imperfect due to variation and convergence.

Gene pool isolation

The separation of gene pools between populations, preventing genetic exchange and enabling divergence.

Evolutionary change in gene pools

Genetic changes accumulated in isolated populations over time, leading to divergence.

Reproductive isolation

Barriers that prevent interbreeding or fertilization between populations, contributing to speciation.

Allopatric speciation

Speciation that occurs when populations are geographically separated, allowing independent evolution.

Subspecies

A population within a species that has distinct traits but can interbreed with other populations of the same species.

Hybrid

Offspring resulting from mating between individuals of different species or populations; fertility varies.

Mule

A hybrid between a horse and a donkey, typically sterile due to chromosome-number differences.

Lock-and-key mating (prezygotic isolation)

Mating succeeds only when male and female signals and structures fit; otherwise mating is unlikely.

Geographic isolation

Physical barriers (rivers, lakes, habitat changes) that separate populations and limit gene flow.