Heterotrophs include animals, protistans, bacteria, and fungi. D. Carbon and energy enter life processes by photosynthesis and in turn are released by glycolysis and aerobic respiration . A. Sources of Energy and Materials for the Reactions 1. Where the Reactions Occur 1. Both stages of photosynthesis occur in the chloroplast.
Pigments absorb light energy and give up electrons.
Electrons are replaced in the molecules that first gave them up. Overview a. Electrons expelled from a chlorophyll molecule go through one or two electron transport systems. Oxygen is a by-product of photosynthesis since it is released when water is split by sunlight. Light-Independent Reactions A. Overview 1. Atmospheric air, which provides the carbon and oxygen from carbon dioxide.