Chapter 5 Outline
Case Study: Toolmaking Crows
Sources of Energy
CONCEPT 5.1 Organisms obtain energy from sunlight, from inorganic chemical compounds, or through the consumption of organic compounds.
Autotrophy
CONCEPT 5.2 Radiant and chemical energy captured by autotrophs is converted into stored energy in carbon–carbon bonds.
- Chemosynthesis fixes energy from inorganic compounds
- Photosynthesis is the powerhouse for life on Earth
- BOX 5.1 How Do Plants Cope with Too Much Light?
Photosynthetic Pathways
CONCEPT 5.3 Environmental constraints resulted in the evolution of biochemical pathways that improve the efficiency of photosynthesis.
- Photorespiration lowers the efficiency of photosynthesis
- C4 photosynthesis lowers photorespiratory energy loss
- CAM photosynthesis enhances water conservation
Heterotrophy
CONCEPT 5.4 Heterotrophs have evolved mechanisms to acquire and assimilate energy efficiently from a variety of organic sources.
- Food sources differ in their chemistry and availability
- Heterotrophs obtain food using diverse strategies
- Optimal foraging theory predicts that foraging animals will maximize their energy gain
Case Study Revisited: Toolmaking Crows
Connections in Nature: Tool Use and Innovative Foraging
