Biology Chapter One: A View of Life

Vocabulary terms covering the levels of biological organization, characteristics of life, taxonomy, and the scientific method as presented in Chapter One.

Biology

The scientific study of life.

Atom

Smallest unit of an element composed of electrons, protons, and neutrons.

Molecule

Union of two or more atoms; can include one or more elements.

Cell

The structural and functional unit of all living things.

Tissue

A group of cells with a common structure and function.

Organ

Composed of tissues functioning together for a specific task.

Organ System

Composed of several organs working together.

Organism

An individual; complex individuals contain organ systems.

Species

A group of similar, interbreeding organisms.

Population

Organisms of the same species in a particular area.

Community

Interacting populations in a particular area.

Ecosystem

A community plus the physical environment.

Biosphere

Regions of the Earth's crust, waters, and atmosphere inhabited by living organisms.

Metabolism

The energetic chemical processes inside a cell.

Homeostasis

A dynamic equilibrium maintained by physiological processes that describes the balance of conditions in an organism.

DNA (deoxyribonucleic acid)

A molecule which encodes the instructions for all functions of the organism.

Mutation

Imperfect copying of DNA that allows for variations and accounts for the variation seen in organisms.

Evolution

Common decent with modification.

Adaptations

Variations in a population that improve fitness, which is the ability to survive and reproduce.

Natural Selection

The process where greater fitness leads to a greater chance of survival and reproduction.

Producers

Organisms like plants and algae that photosynthesize, capturing energy from sunlight to make molecules.

Consumers

Organisms that eat to survive, breaking down molecules for energy and biomass.

Biodiversity

The total number and relative abundance of variable genes, species, and the variety of ecosystems in which they live.

Extinction

The death of the last member of a species or taxa.

Taxonomy

Discipline of biology that identifies, names, and classifies organisms.

Systematics

The study of evolutionary relationships between organisms.

Binomial Nomenclature

The standard two-part naming scheme for identification of specific organism types where the first word is the genus and the second is the species.

LUCA

Last Universal Common Ancestor; the common ancestor from which all organisms derive.

Prokaryotes

Single-cellular organisms whose cells are small, lack a nucleus, and lack other membrane-bound internal compartments.

Eukaryotes

Organisms with cells containing a membrane-bound nucleus and typically other endomembranes; can be single or multicellular.

Scientific Method

A standardized process of investigation involving observation, hypothesis, experiments, data collection, and conclusion.

Hypothesis

A tentative, testable explanation for what was observed, developed through inductive reasoning.

Experimental / Independent variable

The factor being tested in an experiment.

Responding / Dependent Variable

The factor affected by the test, which is measured and used as data for analysis.

Control Group

A group in an experiment not exposed to the experimental variable, used as a comparison.

Scientific Theory

Concepts that join two or more well-supported and related hypotheses, supported by a broad range of observations and data.

Scientific Principle / Law

A widely accepted set of theories with no serious challenges to validity.

Climate Change

Changes in the normal cycles of the climate attributable to human activities, such as an imbalance in carbon cycling.

Global Warming

The increase in temperature via the greenhouse effect caused by an increase in $CO_2$.