BLG143: Biology and the Tree of Life

Vocabulary practice flashcards covering fundamental concepts, definitions, historical experiments, and key biological principles from BLG143 Chapter 1: Biology and the Tree of Life.

Dish With One Spoon

A treaty between the Anishinaabe, Mississaugas, and Haudenosaunee that bound them to share the territory and protect the land.

Science

A process for understanding the natural, observable world by asking questions answered through measuring things and collecting data.

Hypothesis

A testable statement that proposes an explanation for an observed phenomenon.

Theory

An explanation for a very general class of phenomena or observations that is supported by and consistent with most or all available data.

Cell

A highly organized compartment bounded by a plasma membrane and containing concentrated chemicals in an aqueous solution.

Cell Theory

The unifying biological principle stating that all organisms are made of cells and all cells come from preexisting cells.

Spontaneous Generation

The hypothesis that organisms could arise spontaneously under certain conditions from nonliving materials, such as bacteria and fungi spoiling milk or wine.

Descent with Modification

The phrase used by Charles Darwin to describe how the characteristics of species can be modified from generation to generation.

Evolution

A change in the characteristics of a population over time.

Population

A group of individuals of the same species living in the same area at the same time.

Natural Selection

The primary mechanism of evolution that occurs when individuals vary in heritable traits and certain versions of those traits increase reproductive success in a given environment.

Fitness

The ability of an individual to produce viable offspring relative to other individuals in the population.

Adaptation

A heritable trait that increases the fitness of an individual in a particular environment.

Speciation

The evolutionary process that takes place when populations diverge to form new species.

Chromosome Theory of Inheritance

The theory proposed in 1902 by Walter Sutton and Theodor Boveri stating that hereditary information is encoded in genes located on chromosomes.

Gene

A hereditary unit located on a chromosome consisting of a segment of DNA that codes for a functional cell product.

Deoxyribonucleic Acid (DNA)

A double-stranded helical hereditary molecule composed of four chemical building blocks (adenine, thymine, cytosine, and guanine) encoding information needed for growth and reproduction.

Central Dogma

The biological principle describing the directional flow of genetic information in cells: DNA codes for RNA, which in turn codes for proteins.

Adenosine Triphosphate (ATP)

The molecule that organisms acquire and store as chemical energy to power cellular reactions and processes.

Tree of Life

A genealogical family tree of all organisms describing relationships among species, originating from a single common ancestor at its base node.

Phylogeny

The actual genealogical and evolutionary relationships among all organisms.

Phylogenetic Tree

A graphical branching diagram constructed from genetic data that illustrates estimated evolutionary relationships among species.

Eukaryotic Cell

A cell that possesses a distinct membrane-bound nucleus and specialized internal compartments.

Prokaryotic Cell

A cell lacking a membrane-bound nucleus, characteristic of organisms belonging to Domain Bacteria and Domain Archaea.

Taxonomy

The scientific discipline and effort devoted to naming and classifying organisms.

Taxon

Any designated, named group of organisms in a formal classification system.

Genus

A taxonomic category comprising a closely related group of species, always capitalized and italicized in scientific nomenclature.

Species

A distinct, identifiable type of organism whose members regularly breed together or share distinct, identifiable characteristics.

Pedometer Hypothesis

The hypothesis stating that Saharan desert ants navigate back to their nest by keeping track of their stride number and stride length to determine homebound distance.

Null Hypothesis

A hypothesis stating that the experimental treatment or variable has no effect, or that the observed phenomena are independent of one another.

Control Group

A baseline group in an experiment (such as normal, unmanipulated ants) kept under identical conditions to eliminate confounding variables and confirm that observed changes are due to the experimental manipulation.