BI110 Study Guide - Final Guide: Anaerobic Respiration, Heterotroph, Phototroph
Document Summary
Plant, algae, and photosynthetic bacteria use energy from sunlight to generate sugar molecules using photosynthesis. Heterotrophic consumers: must acquire the chemical energy they need by ingesting or absorbing organic molecules from other organisms. In both autotrophs and heterotrophs, cellular respiration is the process that releases energy through the breakdown of food sources. This energy is then used to fuel cell processes. Producers also undergo cellular respiration to break down organic compounds they have produced. Carbohydrates, fats, and proteins are metabolized via cellular respiration into sugars, fats, amino acids: 1 g of fat = 9 kcal or 38 kj, 1 g carbs/protein = 4 kcal. Energy flows into an ecosystem from the sun and moves from producers to consumers through a food web. Each level of energy transfer down the food chain has a 10% efficiency (usually) Environment reflects this need: large # of producers, smaller # of primary consumers, even smaller # of secondary consumers.
