BIOL 1082 Lecture Notes - Lecture 34: Heterotroph, Limiting Factor, Photic Zone

• School: UC
• Department: Biological Sciences
• Course: BIOL 1082
• Professor: Kinkle

Document Summary

Constant energy input and constant energy output: nutrient cycling: matter, like energy, cannot be created nor destroyed (law of conservation of mass). Most autotrophs are photosynthetic organisms that use light energy to synthesize sugars and other organic compounds, which they use as fuel for cellular respiration and as building material for growth. Organisms in trophic levels about the primary producers are heterotrophs, which depend directly or indirectly on the outputs of primary producers for their source of energy. Another group of heterotrophs is the detritivores, or decomposers (prokaryotes and fungi). Detritus is nonliving organic material (remains of dead organisms, feces, fallen leaves, and wood). Many detritivores are in turn eaten by secondary and tertiary consumers. A limiting nutrient is a element that must be added for production to increase; they limit primary production: the nutrient most often limiting marine production is either nitrogen or phosphorus.