BIO 111 Chapter 1: Evolution, the Themes of Biology, and Scientific Inquiry

Cell theory

All living organisms are composed of cells, the basic unit of life, and new cells arise from existing cells.

Levels of biological organization

A hierarchical framework from biosphere to molecules that describes how life is organized.

Biosphere

All life on Earth and the places where life exists.

Ecosystem

All living things in a given area plus the nonliving components with which they interact.

Community

The array of populations inhabiting a particular ecosystem.

Population

All individuals of a species living within a defined area that interbreed.

Organism

An individual living thing.

Organ

A body part made of multiple tissues with a specific function.

Tissue

A group of cells that work together to perform a specialized function.

Cell

The basic unit of life; some organisms are unicellular, others multicellular.

Molecule

A chemical structure of two or more atoms held together by chemical bonds; building blocks of life.

DNA

The genetic material; a double stranded molecule encoding genes and directing inheritance.

Gene

A unit of inheritance; a DNA sequence that directs production of a product or function.

Genome

The entirety of genetic material in an organism.

Genomics

The study of whole sets of genes in one or more species.

Proteomics

The study of the sets of proteins and their properties.

Proteome

The entire set of proteins expressed by a given cell, tissue, or organism.

Bioinformatics

Use of computational tools to store, organize, and analyze large biological data sets.

Producers

Photosynthetic organisms that convert light energy into chemical energy; base of the food chain.

Consumers

Organisms that feed on other organisms or their remains.

Metabolism

Chemical processes that sustain life by transforming energy and materials.

Homeostasis

The tendency to maintain a relatively stable internal environment.

Feedback regulation

The output of a process regulates that process, helping maintain balance.

Energy processing

Acquisition and use of energy to power life processes.

Evolution

Biological change over time with descent from common ancestors and adaptation.

Natural selection

Mechanism by which certain traits increase survival and reproduction, shaping populations.

Domains of life

Three major lines of life: Bacteria, Archaea, and Eukarya.

Bacteria

A domain of prokaryotes; unicellular organisms lacking a nucleus.

Archaea

A domain of prokaryotes; often extremophiles with unique molecular features.

Eukarya

Domain of organisms with eukaryotic cells; includes plants, fungi, animals, and protists.

Protists

A diverse group of mostly single-celled or simple multicellular eukaryotes.

Plantae

Kingdom of multicellular photosynthetic plants within Eukarya.

Fungi

Kingdom of usually multicellular decomposers within Eukarya.

Animalia

Kingdom of multicellular animals within Eukarya.

Charles Darwin

Proposed natural selection as the mechanism by which evolution occurs.

Scientific inquiry

The search for information and explanations of natural phenomena through observation and data.

Inductive reasoning

Deriving generalizations from a large number of specific observations.

Deductive reasoning

Predicting specific outcomes from general principles.

Hypothesis

A testable explanation or educated guess that leads to predictions.

Experiment

A controlled test conducted to investigate a hypothesis.

Independent variable

The factor deliberately changed in an experiment.

Dependent variable

The factor measured in response to changes in the independent variable.

Theory

A well-supported explanation that can generate many testable hypotheses.

Scientific method

A systematic process: define question, form predictions, collect and analyze data, draw conclusions.

Observations (qualitative)

Qualitative descriptions of phenomena such as colors or symptoms.

Observations (quantitative)

Quantitative data: numerical measurements and calculations.