Life Science 11: Evolution and Genetics Review

Comprehensive vocabulary flashcards covering molecular genetics, evolutionary mechanisms, evidence of evolution, and evolutionary tempos from the Life Science 11 review notes.

DNA (Deoxyribonucleic Acid) Structure

A molecule composed of nucleotides, each consisting of a phosphate group, a sugar, and one of four nitrogenous bases: adenine (A), guanine (G), cytosine (C), or thymine (T).

Steps of DNA Replication

A three-step process to produce copies for daughter cells: 1. Unwind and unzip, 2. Complementary base pairing, 3. Assembly of the sugar-phosphate backbone.

Functions of DNA

To replicate with accuracy during sexual and asexual reproduction, store biological information, and undergo rare changes (mutations).

Gene

A short segment of a DNA strand that codes for a specific trait.

Allele

The different forms that genes can take (for example, blue or green eye colours).

Evolution

The process by which modern organisms descended from ancient organisms.

Speciation

A process explaining how new species evolve from old ones, such as seen in Darwin's finches.

Natural Selection

Any change in the relative frequency of alleles in the gene pool of a population.

Gene Flow (Migration)

The transfer of alleles of genes from one population to another, potentially driving evolution as migrating individuals adapt and breed in a new location.

Genetic Drift

Any change in the allelic frequencies of a population that occurs strictly by chance.

Mutation

A change that occurs when DNA is not copied correctly, altering one or more bases (A, C, T, or G) or adding an extra nitrogenous base.

Non-Random Mating

A condition in which mate selection within a population is not random, causing the frequency of alleles to change.

Fitness

A measure of survival in the struggle for existence, where only individuals with characteristics well-suited to their environment survive.

Divergent Evolution

The process in which an ancestral species gives rise to a diversity of new species, such as Darwin's finches diversifying across islands with different food sources.

Convergent Evolution

The process in which species from different evolutionary lines change to resemble one another because they adapt to similar environments (e.g., wings evolving separately in butterflies, bats, and birds).

Fossil Record

Evidence for evolution found in layers of sediment laid down over millions of years, showing gradual changes in organism morphology.

Embryology

Evidence for evolution demonstrating that all vertebrates exhibit homologous structures during early stages of development.

Homologous Structures

Similar anatomical structures inherited from a common ancestor that have evolved to serve different functions.

Vestigial Structures

Anatomical structures that are reduced or non-functional forms of structures that are functional in other organisms.

Gradualism

An evolutionary model in which biological change occurs slowly and gradually over long periods of time.

Punctuated Equilibrium

An evolutionary model characterized by long periods of no change interrupted by short periods of significant change.