Ecosystem Nutrition and Energy Flow

Internal refers to something situated on the inside of an organism.

External refers to something located on the outside or surface of an organism.

Metabolic processes generate waste products that must be removed to prevent toxicity and maintain homeostasis.

Living organisms require specific resources to maintain life processes, including energy (food), water, air for respiration, and shelter for protection.

Fungi are heterotrophs that secrete digestive enzymes onto organic matter and absorb the resulting nutrients, a process known as saprotrophic nutrition.

Heterotrophs are organisms that cannot synthesize their own food from inorganic sources and must consume other organisms to obtain energy.

Parasitic nutrition involves an organism living on or inside another host organism and deriving nutrients from it, typically causing harm but not immediate death.

Aquaculture is the farming of aquatic organisms such as fish, crustaceans, mollusks, and aquatic plants. It involves cultivating these populations under controlled conditions.

Ecosystems contain complex food webs, not just a single food chain. Multiple organisms interact and consume various other organisms, creating a web of energy transfer.

Food chains begin with producers, which are organisms that can make their own food through photosynthesis, specifically green plants.

Producers are organisms that produce their own food using sunlight, water, and carbon dioxide; green plants are the primary example.

Autotrophs (producers like plants) are the base of every food chain because they convert solar energy into chemical energy.

Decomposers (such as bacteria and fungi) break down dead organic matter into nutrients, forming humus in the soil.

Chemoheterotrophs derive both their energy and their carbon from organic compounds. Photoautotrophs use light and CO2, while chemoautotrophs use inorganic chemicals and CO2.

Organisms that produce their own food through photosynthesis are called producers or autotrophs.