| A | B |
| soil (component) | a mixture of mineral matter, organic matter, water and air |
| soil (traditional) | material which nourishes and supports growing plants |
| soil | a naturally occurring mixture of mineral and organic matter with a definite form, structure, and composition |
| average soil sample | 45% minerals, 25% water, 25% air, and 5% organic matter |
| pore space | the voids between the mineral particles of soil |
| macropores | larger voids in soil which allow air and water to move through them rapidly |
| organic matter | living organisms, humus, residue, and decomposing organic matter |
| humus | dark colored, sticky residue from the bodies of dead organisms that can be broken down no further; gives soil structure; major source of plant nutrients |
| rhizosphere | interface between the soil and plant roots |
| mycorrhizae | the symbiotic association between the mycelium of a fungus and the roots of certain plants |
| saprophytic fungi | fungi that decompose dead organic matter |
| mycorrhixal fungi | the type of fungi that form symbiotic relationships with plant roots to assist the plant in acquiring nutrients from the soil |
| photosynthesis | carbon dioxide + water + (sunlight) -----> sugar + oxygn + water |
| 6CO2 + 12 H2O ---> C6H12O6 + 6O2 + 6H2O | photosynthesis |
| photosynthesis | how the plant makes sugar (food) |
| by-products of photosynthesis | oxygen (O2) and water (H2O) |
| respiration | the breaking down of the plant sugars to obtain the energy needed for life processes |
| aerobic | occurs in the presence of oxygen |
| anaerobic | occurs in the absence of oxygen |
| autotrophs | organisms that make their own food |
| heterotrophs | consumers; cannot make their own food |