DE Environmental Science - C2 Principles of Science and Systems - Mr. Knowles

blind experiment

Experiment in which those carrying out the experiment don't know, until after the gathering and analysis of data, which was the experimental treatment and which was the control.

closed system

An ecosystem that neither receives nor emits energy or matter to the surrounding environment.

controlled study

Study in which comparisons are made between experimental and control populations that are (as far as possible) identical in every factor except the one variable being studied.

deductive reasoning

Deriving testable predictions about specific cases from general principles.

dependent variable

A variable that is affected by the condition being altered in a manipulative experiment.

disturbances

Periodic destructive events such as fires or floods; changes in an ecosystem that affect (positively or negatively) the organisms living there.

double-blind experiment

A design in which neither the experimenter nor the subjects know, until after the gathering and analysis of data, which was the experimental treatment and which was the control.

emergent properties

Characteristics of whole, functioning systems that are quantitatively or qualitatively greater than the sum of the system's parts.

homeostasis

The maintenance of a dynamic, steady state in a living system through opposing, compensating adjustments.

hypothesis

A provisional explanation that can be tested scientifically.

independent variable

A factor not affected by the condition being altered in a manipulative experiment.

inductive reasoning

Inferring general principles from specific examples.

manipulative experiment

An experiment in which some conditions are deliberately altered while others are held constant to study cause-and-effect relationships.

mean

Average; a representation of the middle of a group; commonly calculated as the sum of values divided by the number of observations.

models

Simple representations of more complex systems.

natural experiment

A study of events that have already happened.

negative feedback

A situation in which a factor or condition causes changes that reduce that factor or condition.

open system

A system that exchanges energy and matter with its environment.

positive feedback

A situation in which a factor or condition causes changes that further enhance that factor or condition.

replication

Repeating studies or tests to verify reliability.

reproducibility

The capacity for a particular result to be observed or obtained more than once.

resilience

The ability of a community or ecosystem to recover from disturbances.

'sample' as a noun

A small portion of a population, used to approximate characteristics of the population.

'sample' as a verb

To collect observations or a small portion of a population, to allow characterization of a population.

science

A process for producing knowledge methodically and logically.

science literacy

An ability to understand basic scientific concepts, methods, and implications.

scientific theory

An explanation supported by many tests and accepted by a general consensus of scientists.

significant figure

Also known as significant digits, a meaningful degree of precision.

state shift

A permanent or long-lasting change in a system to a new set of conditions and relations in response to a disturbance.

statistics

Numbers that describe observations or groups of observations; also a field of study that provides methods of comparing descriptive numbers.

systems

Networks of interactions among many interdependent factors.

throughput

The flow of energy and matter into, through, and out of a system.