Food chain & biomass

producers

organisms that produce their own food (ie. plants, algae, photosynthetic bacteria)

consumers

gains chemical energy from feeding on other organisms

herbivores

feeds on plants only

predators

hunt for food

scavengers

feed on remains

decomposers

feed on organic matter & transform it into inorganic matter to create nutrients

saprotrophs

external digestion by secreting enzymes externally (ie. bacteria, fungi)

detritivores

break down organic matter into smaller pieces (ie. earthworm, shrimp)

parasites

feed on organisms through intrusion

biomass

total amount of organic matter stored in an organism or trophic level

gross productivity

total gain in biomass by an organism

net productivity

remaining biomass after losses during respiration