| Questions | 5 |
| Topics | Consumers, Decomposers, Mantle, Radiation, Respiration |
Most animals consume other organisms to survive. Consumers (heterotrophs) are divided into three types, primary, secondary, and tertiary, based on their place in the food chain.
Decomposers (saprotrophs) are organisms such as bacteria and fungi that break down the organic matter in the dead bodies of plants and animals into simple nutrients.
Mantle makes up 84% of the Earth's volume and has an average thickness of approximately 1,800 miles (2,900 km). It is dense, hot, and primarily solid although in places it behaves more like a viscous fluid as the plates of the upper mantle and crust gradually "float" along its circumference.
Radiation occurs when electromagnetic waves transmit heat. An example is the heat from the Sun as it travels to Earth.
The respiratory system manages respiration which is the process by which blood cells absorb oxygen and eliminate carbon dioxide.