Chapter 15: Our Environment

Flashcards covering environmental science basics, waste classification, ecosystem dynamics, energy flow, and ozone depletion based on Chapter 15.

Environment

The surrounding in which living organisms, including plants, animals, and human beings, live and interact with non-living things like air, water, and land.

Environmental science

The study of organisms in relation to their surrounding.

Pollution

Any undesirable change in the physical, chemical, or biological characteristics of air, land, and water that affects human life adversely.

Pollutant

A substance released into the environment due to natural or human activity which affects the environment adversely, such as Sulphur-di-oxide, carbon-monoxide, lead, and mercury.

Bio-degradable wastes

Substances that are broken down by biological processes or microbial action, such as wood, paper, and leather.

Non-bio-degradable wastes

Substances that are not broken down by biological or microbial action, such as plastic substances and mineral wastes.

Ecosystem

A community of organisms that interact with one another and with the environment, consisting of biotic and abiotic components.

Abiotic Component

The non-living parts of an ecosystem, including air (providing oxygen and carbon dioxide), water (essential for metabolic activities), and soil (a reservoir of nutrients).

Biotic Component

All living beings in an ecosystem, classified into producers, consumers, and decomposers.

Producers

Green plants (autotrophs) that prepare their own food by trapping solar energy through photosynthesis.

Consumers

Animals and other living beings that take food directly or indirectly from plants.

Decomposers

Bacteria and fungi that break down dead remains of plants and animals to channelize raw materials back to the environment.

Food chain

A series of organisms through which food energy flows in an ecosystem, where each organism feeds on the one below it in the series.

Food web

A graphical depiction of feeding connections and interconnected, overlapping food chains within an ecological community that increases ecosystem stability.

Trophic levels

The specific levels an organism holds in a food chain or food pyramid.

Primary Consumer

The second level of a food chain, usually consisting of herbivores like insects, sheep, and cows that eat producers.

Secondary Consumers

The third level of a food chain consisting of carnivores, such as lions, snakes, and cats, that eat primary consumers.

Tertiary Consumers

The fourth level of a food chain consisting of animals that eat secondary consumers.

Predators

Animals at the top of the food chain that have little or no natural enemies and hunt prey for food.

Prey

An animal that predators hunt, kill, and feed on.

Detrivores

Organisms like vultures, worms, and crabs that eat organisms after they have died.

Unidirectional energy flow

The process where energy enters plants from the sun and is passed through a food chain, but energy lost as heat cannot be reused by plants for photosynthesis.

Ten per cent rule

The principle that during the transfer of energy through successive trophic levels, the energy available at each level is only $10\%$ of the previous level.

Ozone ($O_3$)

A molecule formed by three atoms of oxygen that acts as a deadly poison but shields the earth's surface from harmful ultraviolet (UV) radiation at higher atmospheric levels.

Chlorofluorocarbons (CFCs)

Synthetic chemicals used as refrigerants and in fire extinguishers that are linked to the sharp drop in atmospheric ozone levels since the 1980s.

Incineration

The disposal of hazardous bio-medical waste, such as anatomical wastes and toxic drugs, by means of burning.

Deep well injection

A waste disposal method involving pumping hazardous liquids into a well drilled into dry porous material below ground water to remain isolated indefinitely.

Biological magnification

The progressive accumulation of non-degradable chemicals in the individuals of higher trophic levels within an ecosystem.

Recycling

The process of separating materials like rubber, glass, paper, and scrap metal from refuse and reprocessing them for reuse, also known as reclamation of waste.