Chapter 12 – Interactions within Ecosystems (Vocabulary Review)

These vocabulary flashcards summarise the essential terms and concepts related to ecosystem interactions, energy flow, species relationships, and human impacts presented in Chapter 12.

Ecosystem

A community of organisms interacting with one another and with their physical (abiotic) environment.

Biosphere

The global ecosystem; all regions of Earth where life exists.

Population

All organisms of the same species living in a particular habitat at the same time.

Habitat

The natural environment where an organism lives and meets its needs for survival.

Community

Different populations living and interacting together in the same habitat.

Abiotic Factor

Any non-living component of the environment (e.g., light, temperature, water, pH, salinity).

Biotic Factor

Any living component of the environment, including organisms and their interactions.

Adaptation

Structural or behavioural trait that increases an organism’s chance of survival in its environment.

Producer

An organism (usually a green plant or some bacteria) that makes its own food through photosynthesis or chemosynthesis.

Consumer

An organism that obtains energy by feeding on other organisms.

Herbivore

A consumer that feeds exclusively on plants.

Carnivore

A consumer that feeds exclusively on animals.

Omnivore

A consumer that feeds on both plants and animals.

Decomposer

An organism (e.g., fungi, bacteria) that breaks down dead matter and releases nutrients back into the environment.

Scavenger

An animal that feeds on the remains of dead organisms rather than hunting live prey.

Chemoautotroph

A producer (certain bacteria) that synthesises food using chemical energy instead of light (chemosynthesis).

Predator-Prey Relationship

Interaction where one organism (predator) hunts and eats another (prey).

Mutualism

A symbiotic relationship in which both species benefit.

Parasitism

A relationship in which one organism benefits (parasite) and the other is harmed (host).

Food Chain

Linear sequence of organisms through which energy is transferred in the form of food.

Food Web

Interconnected food chains showing multiple feeding relationships in an ecosystem.

Trophic Level

Each step or level in a food chain or food web (producer, primary consumer, etc.).

Energy Flow

One-way transfer of energy through trophic levels, beginning with the sun and ending with decomposers and heat loss.

10 % Rule

Only about 10 % of energy is passed to the next trophic level; about 90 % is lost as heat.

C-HIPPO

Mnemonic for major human threats to biodiversity: Climate change, Habitat destruction, Invasive species, Pollution, Population growth, Over-harvesting.

Climate Change

Long-term alteration of temperature and typical weather patterns, often due to human activities.

Habitat Destruction

Loss or degradation of natural environments, reducing available living space for organisms.

Invasive Species

Non-native organisms that spread rapidly, lack natural predators, and harm native species.

Pollution

Introduction of harmful substances or energy into the environment that cause adverse effects.

Over-harvesting

Unsustainable hunting or extraction of organisms leading to population declines.

Conservation

Protection and sustainable management of natural resources and biodiversity.

Photosynthesis

Process by which producers convert light energy, carbon dioxide, and water into glucose and oxygen.

Respiration

Process by which organisms break down food molecules to release energy, producing carbon dioxide and water.

Salinity

Concentration of dissolved salts in water or soil, influencing what organisms can live there.

pH

Measure of acidity or alkalinity of a solution; affects organism survival.

Mineral Salts

Inorganic nutrients (e.g., nitrates, phosphates) required by organisms for growth and metabolism.

Data Logger

Electronic device that records abiotic factors (e.g., temperature, light intensity) over time.