Environmental Science Mega Reviewer Modules 1–5

Vocabulary flashcards covering key terms and definitions from Modules 1–5 of Environmental Science Mega Reviewer.

Science

Systematized knowledge gained from observation and experimentation; used to solve real-world problems through empirical study.

Environment

Surroundings that include air, water, land, energy, and both living and non-living components.

Environ

Surroundings.

Atmosphere

The air layer surrounding Earth, divided into Troposphere, Stratosphere, Mesosphere, Thermosphere, and Exosphere.

Troposphere

Lowest layer of the atmosphere (up to ~12 km); weather and clouds form; contains most water vapor and aerosols; aviation occurs here.

Stratosphere

Layer from ~12–50 km; contains the ozone layer; temperature generally increases with altitude; jet aircraft fly at its lower boundary.

Mesosphere

Layer from ~50–80 km; coldest layer (~−85°C); noctilucent clouds form; meteors burn up here.

Thermosphere

Layer from ~80–700 km; contains the ionosphere; auroras occur here; ISS orbits within this layer.

Exosphere

Outer edge of the atmosphere (≈700–10,000 km); gradually merges with space; satellites orbit here.

Ionosphere

Region within the Thermosphere that contains ions and is important for radio communications and auroras.

Hydrosphere

All water bodies and the water cycle.

Lithosphere

Earth’s crust, including soil, rocks, and mountains.

Biosphere

All living organisms and their interactions.

Environmental Science (definition)

An interdisciplinary field combining ecology, physics, chemistry, biology, geology, and more.

Environmental Degradation

Decline in environmental quality due to resource depletion and environmental stress.

Land/Soil degradation

Deterioration of soil quality from farming practices and chemicals.

Water degradation

Pollution and depletion of water resources from dumping and industrial wastes.

Air degradation

Air quality decline, including ozone depletion.

Resources degradation

Overpopulation and overuse of natural resources leading to depletion.

Biodiversity degradation

Threats such as deforestation impacting biodiversity.

Public Awareness (in env. context)

Education as key to promoting eco-friendly behavior.

RA 9003

Ecological Solid Waste Management Act of 2000 (Philippines).

RA 9275

Philippine Clean Water Act of 2004.

RA 8749

Philippine Clean Air Act of 1999.

RA 6969

Toxic Substances, Hazardous and Nuclear Waste Control Act of 1990.

RA 9512

National Environmental Awareness and Education Act of 2008.

RA 10121

Philippine Disaster Risk Reduction and Management Act of 2010.

RA 9729

Climate Change Act of 2009.

Sustainable Development

Meeting present needs without compromising the ability of future generations to meet theirs.

Three Pillars of SD

People (social equity), Planet (environmental protection), Profit (economic sustainability).

SDGs

Sustainable Development Goals; UN global targets to end poverty, protect the planet, and promote peace and prosperity by 2030.

No Poverty

End poverty (SDG 1).

Zero Hunger

End hunger (SDG 2).

Good Health and Well-being

Promote health and well-being (SDG 3).

Quality Education

Inclusive education for all (SDG 4).

Gender Equality

Empower women and ensure equality (SDG 5).

Clean Water and Sanitation

Access to safe water and sanitation (SDG 6).

Clean Energy

Affordable, reliable energy (SDG 7).

Decent Work and Economic Growth

Jobs and growth (SDG 8).

Industry, Innovation, and Infrastructure

Build resilient infrastructure; foster innovation (SDG 9).

Reduced Inequality

Fair opportunities and reduced inequalities (SDG 10).

Sustainable Cities and Communities

Safe, inclusive urban spaces (SDG 11).

Responsible Consumption and Production

Use resources wisely (SDG 12).

Climate Action

Take urgent action to combat climate change (SDG 13).

Life Below Water

Protect oceans and marine resources (SDG 14).

Life on Land

Protect ecosystems and biodiversity (SDG 15).

Peace, Justice, and Strong Institutions

Promote peaceful, just societies (SDG 16).

Partnerships for the Goals

Global cooperation to achieve SDGs (SDG 17).

Levels of Biological Organization

A hierarchical sequence: Atom → Molecule → Cell → Tissue → Organ → Organ System → Organism → Population → Community → Ecosystem → Biome → Biosphere.

Atom

Basic unit of matter.

Molecule

Two or more atoms bonded together.

Cell

Basic unit of life.

Tissue

Group of similar cells performing a function.

Organ

Structure composed of tissues performing a specific function.

Organ System

Group of organs working together for a common function.

Organism

An individual living being.

Population

Group of individuals of the same species in a defined area.

Community

Multiple interacting populations in a shared location.

Ecosystem

A community of organisms interacting with its physical environment.

Biome

Distinct geographic region with specific climate, vegetation, and animal life.

Biosphere

all life-supporting regions of Earth.

Ecology

Study of interactions among organisms and their environment, focusing on ecosystems.

Terrestrial ecosystem

Land-based ecosystem.

Aquatic ecosystem

Water-based ecosystem.

Artificial Ecosystem

Human-made; controlled biotic and abiotic factors (e.g., urban areas, artificial ponds).

Natural Ecosystem

Operates without human interference; maintained by natural processes.

Abiotic components

Non-living parts: sunlight, water, soil, temperature, air.

Biotic components

Living parts: producers, consumers, decomposers.

Producers (Autotrophs)

Organisms like plants and algae that synthesize their own food.

Consumers (Heterotrophs)

Organisms that eat others: herbivores, carnivores, omnivores.

Decomposers

Organisms like bacteria, fungi, and earthworms that break down dead matter.

Energy Flow

Energy moves sun → producers → consumers → decomposers; about 10% transfers to next trophic level.

Food Chain

Linear sequence of energy transfer.

Food Web

Interconnected food chains in an ecosystem.

Ecological Succession

Gradual change in species composition over time in an area.

Primary Succession

Occurs in lifeless areas starting from bare rock/soil formation.

Secondary Succession

Occurs after a disturbance in previously inhabited areas.

Clement’s Six Phases of Succession

Nudation, Migration, Ecesis, Competition, Reaction, Stabilization.

Nudation

Bare site formation due to disturbance.

Migration

Arrival of seeds or propagules.

Ecesis

establishment and growth of vegetation.

Competition (in succession)

Species compete for limited resources.

Reaction

Vegetation alters the environment, triggering change.

Stabilization

Formation of a stable climax community.

Biodiversity

Variety of life forms: genetic, species, ecological, and functional diversity.

Functional Diversity

Diversity of biological and chemical processes that support life (energy flow, nutrient cycling).

Species Diversity

Variety and abundance of species in communities.

Ecological Diversity

Range of terrestrial and aquatic ecosystems.

Genetic Diversity

Variation of genes within a species or population.

Values of Biodiversity (Consumptive)

Food, medicine.

Values of Biodiversity (Productive)

Commercial goods.

Values of Biodiversity (Social & Ethical)

Cultural and spiritual significance.

Values of Biodiversity (Aesthetic)

Ecotourism and natural beauty.

Endemism

High endemism; a large proportion of species are native to a single region (e.g., Philippines).

HIPPO

Major threats to biodiversity: Habitat destruction, Invasive species, Pollution, Human overpopulation, Overharvesting.

Habitat Destruction

Loss of natural habitats due to deforestation, urbanization, etc.

Poaching

Illegal killing/trade of endangered species.

In-situ Conservation

Protecting species within their natural habitats (e.g., national parks, biosphere reserves).

Ex-situ Conservation

Protecting species outside their natural habitats (e.g., zoos, seed banks).

Darwin’s Theory of Evolution

Evolution occurs through natural selection.