The Science of Biology Flashcards

Vocabulary terms and definitions covering the fundamental concepts of biology, the scientific method, evolutionary theory, and unifying biological themes.

Biology

The study of life that unites natural science.

Living systems

Complex chemical systems on earth that show hierarchical organization.

Cellular organization

A characteristic of all living organisms stating they are composed of one or more cells.

Ordered complexity

A characteristic of life where all living things are both complex and highly ordered.

Sensitivity

A characteristic of living organisms involving response to stimuli.

Growth, development, and reproduction

A characteristic of life where organisms increase in size, change over their lifespan, and produce offspring.

Energy utilization

A characteristic of life where organisms take in energy and use it to perform many kinds of work.

Homeostasis

A characteristic of life involving the maintenance of relatively constant internal conditions that are different from their environment.

Evolutionary adaptation

A characteristic of life where organisms evolve adaptations to their environments over time.

Cell

The basic unit of life within the hierarchical organization.

Organismal Level

The hierarchy consisting of Atoms $\rightarrow$ Molecules $\rightarrow$ Organelles $\rightarrow$ Cells $\rightarrow$ Tissues $\rightarrow$ Organs $\rightarrow$ Organ systems.

Populational Level

The hierarchy consisting of Population $\rightarrow$ Species $\rightarrow$ Community $\rightarrow$ Ecosystem $\rightarrow$ Biosphere.

Science

An interdisciplinary field that aims to understand the natural world through observation and reasoning.

Deductive reasoning

The use of general principles to make specific predictions.

Inductive reasoning

The use of specific observations to develop general conclusions.

Hypothesis

A possible explanation for an observation that must be tested for validity and allows for predictions to be made.

Experiment

A test of a hypothesis that evaluates one variable at a time and includes a control versus a test.

Spontaneous Generation Hypothesis

The discredited idea that living organisms will spontaneously generate from nonliving organic molecules in broth.

Germ Hypothesis

The idea that preexisting microorganisms present in the air contaminate nutrient broth.

Natural selection

The mechanism for evolution proposed by Charles Darwin in his book Origin of Species.

Descent with modification

The term used by Darwin to describe the process of evolution where characteristics of similar species vary from place to place.

Geometric progression

The rate at which populations of plants and animals increase, as noted by Thomas Malthus (e.g., $2, 6, 18, 54$).

Arithmetic progression

The rate at which humans can increase their food supply, according to Thomas Malthus (e.g., $2, 4, 6, 8$).

Homologous

Structures having the same evolutionary origin but differing in structure and function, such as vertebrate forelimbs.

Analogous

Structures with different evolutionary origins that have the same purpose, such as butterfly and bird wings.

Phylogenetic trees

Diagrams based on tracing the origin of particular nucleotide changes to reconstruct an evolutionary history.

Cell Theory

A unifying theme stating all organisms are composed of cells, the cell is the basic unit of life, and all cells come from preexisting cells.

DNA (Deoxyribonucleic acid)

The molecular basis of inheritance composed of nucleotides ($A, G, C, T, U$) that carries cellular information.

Gene

A distinct unit of information within the DNA.

Genome

The entire set of DNA instructions for an organism.

Bacteria

A domain of life consisting of single-celled prokaryotes.

Archaea

A domain of life consisting of single-celled prokaryotes that are distinct from bacteria.

Eukarya

A domain of life consisting of single-celled or multicellular eukaryotes.

Evolutionary conservation

The principle that some characteristics are preserved from a simple creature about $3.5$ BYA, reflecting their fundamental role.

Nonequilibrium state

The state of living systems as open systems that require a constant supply of energy.

Emergent properties

Novel properties that arise from the way in which components (molecules, cells, individuals) interact at different levels of organization.