8th Grade Science - Vocabulary Flashcards (Study Guide Based)

A comprehensive set of vocabulary flashcards covering natural hazards, ecosystems, human impacts, evolution, and Earth systems based on the study guide notes.

Flood

An overflow of water that covers land that is usually dry, often caused by heavy rain, dam break, or storm surge.

Drought

A prolonged period of unusually low precipitation leading to water shortages and stressed ecosystems.

Tsunami

A series of large ocean waves caused by underwater earthquakes, landslides, or volcanic activity.

Tornado

A violently rotating column of air that extends from a thunderstorm to the ground; intensity is measured by the Fujita scale.

Hurricane

A large tropical cyclone with strong winds and heavy rain; called a typhoon in the western Pacific and cyclones in the Indian Ocean.

Meteorite

A fragment of rock or metal from space that survives passage through the atmosphere and lands on Earth.

Landslide

The movement of rock, earth, or debris down a slope due to gravity, often triggered by rain, earthquakes, or erosion.

Earthquake

Sudden shaking of the ground caused by movement of tectonic plates along faults.

Wildfire

Uncontrolled fire in vegetation that spreads rapidly and can be influenced by weather and drought.

Catastrophic event

A major, sudden, widespread event that causes extensive damage and disruption.

Natural disaster

A natural hazard that has become destructive to life, property, and ecosystems.

Fujita scale

A scale (F0–F5) used to rate tornado intensity based on damage patterns.

Richter scale

A scale that measures the magnitude (strength) of earthquakes based on seismic waves.

Biodiversity

The variety and variability of life in an area, including species richness, genetic diversity, and ecosystem diversity.

Invasive species

A non-native species that spreads widely and harms native ecosystems, economies, or health.

Native species

species that are originally occurring in an area and adapted to local conditions.

Non-native (nonnative) species

A species introduced to a new area by humans or other means; may become invasive.

Pollinator

An organism (often bees) that facilitates plant reproduction by transferring pollen.

Acid rain

Precipitation with elevated acidity caused by air pollutants (e.g., sulfuric and nitric acids) that can harm ecosystems.

Biocontrol

Biological control; using natural enemies (like insects) to manage pest populations.

Greenhouse effect

Warming of the Earth's surface caused by heat-trapping gases in the atmosphere; amplified by human activities.

Ocean pollution

Contamination of oceans by plastics, chemicals, and other pollutants that threaten sea life.

Biodegradable

Capable of being broken down by natural processes, often relatively quickly.

Nonbiodegradable

Not easily broken down by natural processes; persists in the environment.

Fossil fuels

Coal, oil, and natural gas formed from ancient organisms; burning them releases energy and greenhouse gases.

Natural resources

Materials or substances occurring in nature that can be used for economic gain (water, minerals, fuels, etc.).

Ocean acidification

The lowering of ocean pH due to absorption of atmospheric CO2, affecting calcifying organisms.

Surface pollution

Pollution that contaminates rivers, lakes, and coastal surfaces, often from runoff.

Groundwater pollution

Contamination of underground aquifers by chemicals, wastes, or seepage.

Sustainability

Meeting present needs without compromising the ability of future generations to meet theirs; balance ecological, social, and economic factors.

Synthetic materials

Man-made materials created through chemical processes (often from petroleum-based sources).

Petroleum (primary natural resource for plastics)

A fossil fuel refined into fuels and feedstocks for plastics and many chemicals.

Relative dating

Determining the relative age of rocks/fossils based on their position in layers; principle of superposition is key.

Variation

Differences among individuals within a population that can affect survival and reproduction.

Natural selection

Mechanism by which heritable variation leads to differential survival and reproduction.

Charles Darwin

Naturalist who proposed evolution by natural selection (with Alfred Russel Wallace).

Alfred Russel Wallace

Naturalist who independently conceived theory of natural selection similar to Darwin’s.

Evolution

Change in the heritable traits of a population over successive generations.

Erosion

Process by which water, wind, or ice wears away and transports rock and sediment, exposing fossils.

Index fossils

Fossils of organisms that lived for a relatively short, well-known time period and help date rock layers.

Trace fossils

Fossils that show the activity of organisms (footprints, burrows, borings).

Fitness

The ability to survive and reproduce, leading to more offspring in a population.

Archaeopteryx

Early bird-like dinosaur that provides evidence of evolution from dinosaurs to birds.

Vestigial structures

Body parts that have lost most or all of their original function, signaling common ancestry.

Homologous structures

Similar body parts in different species due to shared ancestry, even if they serve different functions.

Analogous structures

Body parts with similar functions in different species but from different evolutionary origins.

Continental drift/plate tectonics

Theory that continents move over time; explains matching fossils, rocks, and mountain ranges across oceans.

Embryology (embryo development)

Similarities in early development among species suggesting common ancestry.

Common ancestry

Two or more species descended from a shared former ancestor.

Conservation biology

Field focused on protecting biodiversity, ecosystems, and the health of the environment.

Petroleum (revisit)

Primary natural resource used to produce plastics and other synthetic materials.

Plate tectonics

Geoscience process describing the movement of Earth's lithospheric plates that shapes resources and landforms.

Greenhouse gas emissions

GHG released by human activities (e.g., burning fossil fuels) increasing the greenhouse effect and warming the planet.

Pollution remediation

Actions to clean up, reduce, or prevent pollution and restore environmental quality.

Ecosystem resilience

The capacity of an ecosystem to recover after a disturbance and maintain its functions.

Earth system interconnections

Interactions among the lithosphere, hydrosphere, biosphere, and atmosphere through energy flow and matter cycles.

Conservation tillage

Agricultural practices that minimize soil disturbance to reduce erosion and maintain soil health.

El Niño

A climate pattern characterized by warmer-than-average Pacific Ocean surface temperatures leading to altered rainfall and weather patterns globally.

Nitrogen (N)

A major component of Earth’s atmosphere (~78%); essential for life and a key factor in atmospheric chemistry.

Earth Overshoot Day

The date when humanity’s demand for ecological resources in a year exceeds what Earth can regenerate in that year.