Environmental Science Midterm

Vocab Only

Ecology

branch of biology that focuses on how living organisms interact with the living and nonliving parts of their environment

Ecosystem

a biological community of organisms with a defined area of land or volume of water that interact with one another and with the nonliving chemical and physical factors in their environment

Ecosystem Services

natural services provided by healthy ecosystems that support life and human economies at no cost

Environment

energy from the sun and all the living and nonliving things which interacts

Environmental Science

study of connections in the natural environment

Environmentalism

a social movement dedicated to protect the earth’s living support system for humans and other species

Natural Capital

natural resources and ecosystem services that keep humans and other species alive and support human economies

Natural Resource

materials and energy provided by nature that are essential or useful to humans

Renewable Resource

a resource that can be used to repeatedly because it is replenished through natural processes as long as it is not used up faster than nature can renew it

Ecological Footprint

the amount of land needed to generate resources per capita

Point Source

single, identifiable sources of pollutants

Nonpoint Source

pollutants that are dispersed and difficult to pinpoint

Ecocentric

Biocentric

Anthropocentric

pH

a measure of acidity

Electromagnetic Radiation

when energy travels from one place to another in the form of waves formed from changes in electrical and magnetic filds

Energy

the capacity to do work or to transfer heat

First Law of Thermodynamics

whenever energy is converted from one form to another (no energy is created or destroyed)

Second Law of Thermodynamics

whenever energy is converted from one form to another, it ends up with less-usable energy

Kinetic Energy

energy associated with motion

Potential Energy

energy stored up

Ecological Tipping Point

when a natural system becomes locked into a positive feedback loop

Feedback Loop (positive v negative)

when an output is fed back into a system as an input

Atmosphere

a spherical mass of air surrounding the earth’s surface that is held to the earth’s gravity

Hydrosphere

contains all the water in the earth’s surface

Geosphere

the earth’s rocks, minerals, and soil

Biosphere

consists of the parts of the stratosphere, hydrosphere, and geosphere where life is found

Stratosphere

the atmospheric layer above the troposphere

Troposphere

contains all the air we breath

Aerobic Respiration

oxygen converts glucose and other organic compounds into carbon dioxide and water

Anaerobic Respiration

breaking down glucose with the absence of oxygen

Carnivore

meat eaters

Consumer

cannot produce their own food

Decomposer

get their nutrients by decomposing waste or remains of plants and animals

Detritivore

get nutrients by feeding on the waste or dead bodies of other animals

Herbivore

plant eaters

Omnivore

eat both plants and animals

Trophic Level

feeding level

Food Chain

a sequence of organisms each serving as a source of nutrients for the next level of organisms

Food Web

a complex network of interconnected food chains

Gross Primary Production

the rate at which an ecosystem’s producers convert solar energy into chemical energy

Net Primary Production

the rate at which producers use photosynthesis to produce and store chemical energy minus the rate at which they use the energy

Biodiveristy

variety of life on earth

Species Diversity

the number and abundance of the different kinds of species living in an ecosystem

Genetic Diversity

variety of genes found in a population or species

Ecosystem Diversity

earth’s diversity of biological communities

Functional Diversity

variety of processes and matter cycling that occur within the ecosystem as species interact with one another

Biome

a large geographical area characterized by specific climate conditions and particular types of plant and animal life

Insurance Hypothesis

high biodiversity enhances ecosystem stability and resilience by providing functional redundancy and asynchronous responses to environmental fluctations

Ecological Niche

the role a species plays within the ecosystem

Habitat

type of ecosystem

Generalist Species

can live different places, eat variety of foods, and can tolerate environmental change

Specialist Species

can only live in one habitat, eat only a few types of food, and can barely tolerate environmental change

Native Species

normally live and thrive in a particular ecosystem

Nonnative Species

migrate into new ecosystems

Keystone Species

regulate populations and pollunate

Indicator Species

provide early warning signs

Data

information to answer a question

Model

approximate physical or mathematical representation that is used to understand or explain behavior of complex natural systems

Peer Review

evaluation of a research manuscript by other experts (peers) in the same field before its publication

Scientific Process

when scientists discover a problem, propose a hypothesis, to explain the data, gather date to test the hypothesis, and modify the hypothesis if needed

Hypothesis

a testable explanation of data collected

Scientific Law

a well-tested and widely accepted description of observations of what we find always happening in the same way in nature

Scientific Theory

a well-tested and widely accepted scientific hypothesis

Mathematical Proof

a step-by-step logical argument that demonstrates a mathematical statement is true

Atom

the smallest unit of matter into which an element can be divided and still have its distinctive chemical properties

Chemical Change/Reaction

a change in the chemical composition of a substance

Physical Change

no change in its chemical compositio

Compound

combination of two or more different elements held together in fixed proportions

Element

a fundamental type of matter with a unique set of properties and that cannot be broken down into simpler substances by chemical means

Organic Molecule

contain at least two carbon atoms combined with atoms of one or more other elements

Resistance

ability to withstand disturbance

Resilience

ability to recover after a disturbance

Nitrogen Fixation

atmospheric nitrogen gas is converted to ammonia

Nitrification

ammonia is converted to nitrates

Assimilation

when plants absorb nitrates and form proteins

Ammonification

when decomposers return nitrogen from dead organisms and waste to the soil as ammonia

Denitrification

denitrifying bacteria converting nitrates back into nitrogen gas

Nitrate

a compound containing nitrogen and oxygen

Internal Validity

control over variables

External validity (generalizability)

the extent to which a study's findings can be applied to a broader group of people or situations