Ecology and Trophic Structure Quiz

Study Notes

Ecology: The study of how organisms interact with each other and their environment.
Environment: The surroundings or conditions in which an organism lives.
Habitat: The specific place where an organism lives within its environment.
Niche: The role an organism plays in its ecosystem, including its interactions with other organisms and its use of resources.

Biotic factors: Living components of an ecosystem (e.g., plants, animals, fungi).
Abiotic factors: Non-living components of an ecosystem (e.g., sunlight, temperature, water, soil).

Trophic structure: The organization of organisms in an ecosystem based on how they obtain energy.
Food chain: A linear sequence of organisms where energy is transferred from one organism to the next.
Food web: A complex network of interconnected food chains within an ecosystem.

Producers (autotrophs): Organisms that make their own food using energy from the sun (photosynthesis) or inorganic chemicals (chemosynthesis).
- Photosynthetic organisms: Green plants that use sunlight to produce organic compounds.
- Chemosynthetic organisms: Bacteria that use inorganic compounds (e.g., hydrogen sulfide) to produce organic compounds.
Consumers (heterotrophs): Organisms that obtain energy by consuming other organisms.
- Primary consumers (herbivores): Consume producers.
- Secondary consumers (carnivores): Consume primary consumers.
- Tertiary consumers: Consume secondary consumers.
- Decomposers (saprotrophs): Break down dead organic matter and release nutrients back to the ecosystem.

Mutualism: A relationship where both organisms benefit.
Commensalism: A relationship where one organism benefits, and the other is neither harmed nor helped.
Predation: A relationship where one organism (predator) kills and consumes another organism (prey).
Parasitism: A relationship where one organism (parasite) lives in or on another organism (host) and benefits at the host's expense.

Trophic Structures describe the transfer of matter and energy between organisms and their environment.
Energy flows in food chains, where energy from food passes from one organism to the next in a sequence.
Each level in a food chain is called a trophic level.
Trophic levels are linked together in a food web, which is a complex network of interconnected food chains.
All ecosystems begin with the sun, the ultimate source of energy.
Organisms are categorized based on their nutritional habits.

Producers, also called autotrophs, are organisms capable of producing their own organic compounds for energy and nutrients.
Most producers are green plants that use photosynthesis to transform sunlight into chemical energy.
Chemosynthetic organisms, typically bacteria, use chemosynthesis to convert inorganic compounds like hydrogen sulfide into organic nutrients in the absence of sunlight.