ABSTRACT
Chapter 21 begins by presenting ecological processes as a machine, highlighting trophic levels and the energy that flows through them with the sun as the ultimate source. The machine is divided into the grazing and detrital food chains. Primary producers, primary consumers, secondary consumers, and tertiary consumers are identified. Energy is defined and electromagnetic radiation is described in detail. The nature of energy as waves and particles is explained. Sound is categorized as mechanical, not electromagnetic radiation. The energy source for clinical use is described regarding ultrasound, CT, MRI, and X-ray. The first and second laws of thermodynamics are explained and dynamics of the Earth’s atmosphere are reviewed. Several graphs show indicators of global warming from an increase of greenhouse gases. Ocean currents as in a conveyor belt are presented, and the characteristics of El Nino events are described.
