Envisci Unit One Test 1

Science

A body of knowledge (facts and explanations) about the natural world and the process used to get that knowledge. 

empirical observations

information detected with the senses - or with equipment that extends our senses.

scientific method

the procedure scientists use to empirically test a hypothesis.

inferences

conclusions drawn based on observations.

hypothesis

a possible explanation for what we have observed that is based on some previous knowledge.

experimental prediction

a statement that identifies what is expected to happen if the hypothesis being tested is correct.

peer review

a process whereby researchers’ work is evaluated by outside experts to determine whether it is of high enough quality to publish.

theory

a widely accepted explanation of a natural phenomenon that has been extensively and rigorously tested scientifically.

observational study

research that gathers data in a real-world setting without intentionally manipulating any variable.

independent variable

the variable in an experiment that a researcher manipulates or changes to see if the change produces an effect.

dependent variable

the variable in an experiment that is evaluated to see if it changes due to the conditions of the experiment.

test group

the group in an experimental study that is manipulated such that it differs from the control group in only one way.

control group

the group in an experimental study to which the test group’s results are compared; ideally, the control group will differ from the test group in only one way.

statistics

the mathematical evaluation of experimental data to determine how likely any difference observed is due to the variable being tested.

correlation

two things occurring together but not necessarily having a cause-and-effect relationship.

cause-and -effect relationship

an association between two variables that identifies one (the effect) occurring as a result of or in response to the other (the cause)

policy

a formalized plan that addresses a desired outcome or goal.

precautionary principle

acting in a way that leaves a safety margin when the data are uncertain or severe consequences are possible.

information literacy

the ability to find and evaluate the quality of information.

primary source

information source that presents original data or firsthand information

secondary source

information source that presents and interprets information solely from primary sources.

tertiary source

information source that uses information from at least one secondary source

literacy media

the ability to evaluate digital sources of information.

fake news

false information

misleading news

information that contains some truth but may be incomplete or out of context and/or contain false information.

satire

intentionally outrageous to make a point (not saying what they mean)

logical fallacies

arguments that attempt to sway the reader without using reasonable evidence.

hasty generalization

draws a broad conclusion on too little evidence

red herring

presents extraneous information that does not directly support the claim but that might confuse the reader/listener.

ad hominem attack

attacks the person/group that is presenting the opposite view rather than addressing the evidence

appeal to authority

does not present evidence directly but instead makes the case that an “expert” agrees with the position or claim.

appeal to complexity

a statement or an implication that an issue is too complicated to understand

false dichotomy

the argument sets up an either/or choice that is not valid .

critical thinking

skills that enable individuals to logically assess information, reflect on that information, and reach their own conclusions.

Parts in critical thinking

be skeptical, evaluate the evidence, watch out for author biases, be open-minded.

species

a group of plants or animals that have a high degree of similarity and can generally only interbreed among themselves.

biosphere

the sum total of all of earth’s ecosystem

biome

one of many distinctive types of ecosystems determined by climate and identified by the predominant vegetation and organisms that have adapted to live there.

ecosystem

all of the organisms in a given area plus the physical environment in which, and with which, they interact.

biotic

the living (organic) components of an ecosystem, such as the plants and animals and their waste (dead leaves, feces)

abiotic

the nonliving components of an ecosystem, such as rainfall and mineral composition of the soil.

population

all the individuals of a species that live in the same geographic area and are able to interact and interbreed

community

all the populations (plans, animals, and other species) living and interacting in an area.

matter cycles

movement of life’s essential chemicals or nutrients through an ecosystem

energy flow

the one-way passage of energy through an ecosystem.

sinks

abiotic or biotic components of the environment that serve as storage places for cycling nutrients.

range of tolerance

the range, within upper and lower limits, of a limiting factor that allows a species to survive and reproduce.

photosynthesis

the chemical reaction performed by producers that uses the energy of the Sun to convert carbon dioxide and water into sugar and oxygen.

producer

an organism that coverts solar energy to chemical energy via photosynthesis.

consumer

an organism that obtains energy and nutrients by feeding on another organism

cellular respiration

the process in which all organisms break down sugar to release its energy, using oxygen and giving off CO2 as a waste product.

carbon cycle

movement of carbon through biotic and abiotic parts of an ecosystem via photosynthesis and cellar respiration as well as in and out of other reservoirs, such as oceans, soil, rock, and atmosphere.

nitrogen cycle

a continuous series of natural processes by which nitrogen passes from the air to the soil to organisms and then returns back to the air or soil.

nitrogen fixation

conversion of atmospheric nitrogen into a biologically usable form, carried out by bacteria found in soil or via lightning.

nitrification

conversion of ammonia (NH3) to nitrate (NO3-)

denitrification

conversion of nitrate to molecular nitrogen (N2)

Phosphorus cycle

a series of natural processes by which the nutrient phosphorus moves from rock to soil or water to living organisms and back to soil

community ecology

the study of all the population (pans, animals, and other species) and interacting in the area

habitat

the physical environment in which individuals of a particular species can be found

niche

the role a species plays in its community, including how it gets its energy and nutrients, what habitat requirements it has, and with which other species and parts of the ecosystem it interacts.

niche specialist

a species with very specific habitat or resource requirements that restrict where it can live.

niche generalist

a species that occupies a broad niche because it can utilize a wide variety of resource

food chain

a simple, linear path stating with a plant (or other photosynthetic organism) that identifies what each organism in the oath eats.

food chain

a linkage of all food chains together that shows that many connections in the community.

indicator species

a species that is particularly vulnerable to ecosystem perturbations, and that, when we monitor it, can give us advance warning of a problem.

trophic levels

feeding levels in a food chain.

detritivores

consumers (including worms, insects, and crabs) that eat dead organic material

decomposers

organisms such as bacteria and fungi that break organic matter all the way down to constituent atoms or molecules in a form that plants can take up.

resilience

the ability of an ecosystem to recover when it is damaged or perturbed

species diversity

the variety of species in an area; includes measures of species richness and evenness

species richness

the total number of different species

species evenness

the relative abundance of each species in a community.

ecotones

regions of distinctly different physical areas that serve as boundaries different communities.

edge effect

the change in species diversity that occurs due to different conditions that either attract or repel certain species at an ecotone.

keystone species

a species that impacts its community more that its mere abundance would predict, often altering ecosystem structure.

predation

species interaction in which one individual (the predator) feeds on another (the prey)

competition

species interaction in which individuals are vying for limited resources.

resources partitioning

the use of different parts or aspects of a resource by different species rather that direct competition for exactly the same resource.

symbiosis

a close biological or ecological relationship between two species.

mutualism

a symbiotic relationship among individuals of two species in which both parties benefit.

commensalism

a symbiotic relationship among individuals of two species in which on benefits from the presence of the other but the other is unaffected.

parasitism

a symbiotic relationship among individuals of two species in which one benefits and the other is negatively affected.

restoration ecology

the science that deals with the repair of damaged or disturbed ecosystems

ecological succession

progressive replacement of plant (and the animal species in a community over time due to the changing conditions that the plants themselves create (more soil, shade, etc.).

primary succession

ecological succession that occurs in an rea where no ecosystem existed before (e.g., on bare rock with no soil)

pioneer species

species that move into an area during early stages of succession

secondary succession

ecological succession that occurs in an ecosystem that has been disturbed but not rendered lifeless.

population growth rate

the change in population size over time that takes into account the number of births and deaths as well as immigration and emigration numbers.

zero population growth

the absence of population growth; occurs when birth rates equal rates.

demographic factors

population characteristics such as birth rate that influences changes in population size and composition

desired fertility

the ideal number of children an individual indicates he or she would like to have

total fertility rate

the number of children the average women has in her lifetime

pronatalist pressure

factor that increases the desire to have children

childhood mortality rate

the number of children under 5 years of age who die per every 1000 live births in that year.

replacement fertility

the rat at which children must be born to replace the previous generation

age structure

The percentage of the population that is distributed into various age groups

population momentum

The tendency of a young population to continue to grow even after birth rates drop to replacement fertility.

demographic transition

A theoretical model that describes the expected drop in once-high population growth rates as economic conditions improve the quality of life in a population.

preindustrial

Birth and death rates are high but similar, so population growth is slow or stationary; population size is low.