Energy Flow in the Biosphere - Chapters 4.1 & 4.2

Vocabulary practice flashcards covering ecological levels of organization, energy flow, trophic interactions, limiting factors, and symbiotic relationships from Chapter 4.1 and 4.2.

Species

Organisms that are so similar to one another that they can breed and produce fertile offspring.

Populations

Groups of individuals belonging to the same species living together in a specific area (e.g., a "herd").

Community

Different populations of organisms living together in an area.

Ecosystem

All the organisms that live in a place together with their non-living (abiotic) environment.

Biomes

A group of ecosystems that have the same climate and similar communities.

Biosphere

The portion of the planet in which all life exists (including land, water, and atmosphere), extending from about $8\,\text{km}$ above the Earth's surface to $11\,\text{km}$ below the ocean's surface.

Ecology

The scientific study of interactions of organisms with each other and with their environment.

Biotic Factors

All the living things that an organism interacts with in an environment.

Abiotic Factors

All the non-living physical and chemical components that affect an organism, such as climate, temperature, sunlight, soil, humidity, and wind.

Habitat

The specific area where an organism lives, commonly referred to as an organism's "address."

Niche

The place an organism lives plus the full set of biotic and abiotic interactions it has there (its "occupation"), including what it eats, what eats it, its spatial location, behavioral actions (e.g., hibernating or migrating), and reproduction.

Competitive Exclusion Principle

The ecological rule stating that no two species can share the same niche in the same habitat at the same time.

Autotrophs (Producers)

Organisms that make their own food; green plants serve as the main producers on land, whereas algae serve as the main producers in water.

Photosynthesis

The process by which autotrophs capture solar light energy to convert carbon dioxide and water into carbohydrates and oxygen.

Chemosynthesis

The process by which certain autotrophs produce carbohydrates in the absence of light by using energy stored in the chemical bonds of inorganic molecules (e.g., bacteria in volcanic vents, hot springs, and marshes).

Heterotrophs (Consumers)

Organisms that obtain energy by consuming other organisms.

Herbivores

Heterotrophs that eat only plants.

Carnivores

Heterotrophs that eat only animals.

Omnivores

Heterotrophs that eat both plants and animals.

Detritivores

Heterotrophs that feed on plant and animal remains (e.g., mites, earthworms, snails, crabs).

Decomposers

Organisms that break down and absorb organic matter (e.g., bacteria and fungi).

Food Chain

A series of steps in an ecosystem in which organisms transfer energy by eating and being eaten, flowing from producers (autotrophs) to consumers (heterotrophs).

Food Web

A network that links all the complex feeding relationships and food chains in an ecosystem together.

Trophic Level

Each step in a food chain or food web, with producers always occupying the first level.

10% Rule

The ecological principle that only about $10\%$ of the energy from one trophic level is passed on to the level above, while the remaining energy is utilized for life processes or lost as heat.

Resource

Anything needed by an organism for life, such as nutrients, water, light, and space.

Competition

An ecological interaction between organisms of the same or different species competing with each other for available resources (e.g., food, shelter, mates, territory, and light).

Predation

An interaction between different kinds of organisms in which one captures, hunts, and kills another to supply its energy needs.

Interdependence

The concept that all living and non-living things in an ecosystem are interconnected, such that changing even one thing impacts the whole system.

Limiting Factor

A condition or nutrient that limits population growth because it is in short supply or cycles slowly.

Algal Bloom

A dramatic increase in an algae population that occurs when an aquatic ecosystem receives a large influx of a limiting nutrient (such as fertilizer runoff).

Cooperation

An interaction between organisms of the same species that live together in groups (e.g., herds, packs, colonies, families) to help one another by sharing food, defending each other, grooming, or caring for offspring.

Symbiosis

A close ecological association between two different kinds of organisms living together.

Mutualism

A symbiotic relationship in which both organisms benefit from the interaction ("Good for me - Good for you").

Commensalism

A symbiotic relationship in which one organism benefits while the other is neither helped nor harmed ("Good for me - Doesn't bother you").

Parasitism

A symbiotic relationship in which one organism benefits at the expense of another by causing harm to the host ("Good for me - Hurts you").