Biology Basics: Life, Organization, Evolution, and the Scientific Method

A comprehensive set of vocabulary-style flashcards covering basic biology concepts from life definitions and organization to evolution, the scientific method, and types of natural selection.

Biology

The study of living organisms and their interactions with one another as well as the nonliving parts of their environment.

Abiotic environment

The nonliving components of a habitat, such as soil, air, water, and minerals.

Living organism

Any form of life that exhibits the eight characteristics of life.

Eight characteristics of life

Order/organization, sensitivity to environment, reproduction, adaptation, growth and development, regulation/homeostasis, energy processing, and evolution.

Order and organization

First characteristic; living systems show a hierarchy from cells to biosphere.

Sensitivity to environment

Ability to respond to stimuli; organisms may move toward or away from stimuli.

Reproduction

Ability to produce offspring, enabling genes to be passed to the next generation.

Adaptation

Traits that improve survival and reproduction in a given environment; arise over time.

Growth and development

Increase in size and changes in form guided by genes.

Regulation or homeostasis

Maintenance of stable internal conditions through regulatory processes.

Energy processing

Use of energy to power metabolism; organisms may photosynthesize or consume others.

Evolution

Change in heritable traits in a population over generations, often via natural selection.

Levels of biological organization

Hierarchical order from cells to biosphere: cells, tissues, organs, organ systems, organism, population, community, ecosystem, biosphere.

Cell

Smallest unit of life that can perform all eight characteristics of life.

Prokaryotic cell

Cell without a nucleus or membrane-bound organelles.

Eukaryotic cell

Cell with a nucleus and membrane-bound organelles.

Unicellular organism

An organism composed of a single cell.

Multicellular organism

An organism composed of many cells organized into tissues, organs, and organ systems.

Tissue

Group of similar cells performing related functions.

Organ

Structure made of tissues working together to perform a specific function.

Organ system

Group of organs that work together to perform a major function.

Population

All individuals of the same species living in a defined geographic area.

Community

All populations of different species living in a defined geographic area.

Ecosystem

The living communities plus the nonliving environment (air, water, soil, minerals) in a region.

Biosphere

The global sum of all ecosystems; the planet.

Inductive reasoning

Reasoning from specific observations to a general conclusion.

Deductive reasoning

Reasoning from a general principle to specific predictions.

Observation

Information gathered through the senses or instruments to inform a question.

Hypothesis

A testable, falsifiable explanation for an observation or question.

Prediction

A specific outcome expected if the hypothesis is correct.

Experiment

A test with variables, an experimental group, and a control group; results are analyzed to determine support for the hypothesis.

Variable

A factor in an experiment that can change or be measured (independent, dependent, etc.).

Experimental group

The group in which a variable is deliberately changed during an experiment.

Control group

The unmanipulated reference group used for comparison.

Basic science

Science aimed at understanding fundamental principles without immediate practical application.

Applied science

Science aimed at solving real-world problems; typically builds on basic science.

Oyster restoration (applied science example)

Practical use of basic science knowledge to restore oyster reefs (e.g., using shells or concrete to provide settlement cues for larvae).

Natural selection

Mechanism by which evolution occurs through differential survival and reproduction of individuals with favorable traits.

Stabilizing selection

Natural selection that favors the average trait, reducing extremes.

Directional selection

Natural selection that favors one extreme trait over others, shifting the population.

Diversifying (disruptive) selection

Natural selection that favors extreme variants at both ends of a trait distribution.