Chapter 21, Problem 1AQ

Compare and contrast the carbon, sulfur, and nitrogen cycles in terms of the physiologies of the organisms that participate in the cycle. Which physiologies are part of one cycle but not another?

Summary Introduction

To explain:

The differences between carbon, sulfur, and nitrogen cycle in terms of physiologies of organisms involved in the cycle. Also, explain which physiologies are parts of one cycle but not of other.

Concept introduction:

Carbon cycle may be defined as the biogeochemical cycle in which carbon is exchanged among the biosphere, hydrosphere, geosphere, pedosphere, and atmosphere present on earth. Nitrogen cycle may be defined as a complex biogeochemical cycle by which atmospheric nitrogen is converted into various useful forms important to industrial and biological processes.  Sulfur cycle may be defined as the collection of various processes by which cycling of sulfur occurs to and from the rocks, waterways, and the living system.

Explanation of Solution

The differences between carbon, sulfur, and nitrogen cycle are described as below:

Physiology of all three cycle differs from each other in several respects. Physiology of carbon cycle is very different than nitrogen or sulfur cycle as it involves the process of photosynthesis which requires light for completion of carbon cycle. Such requirement is not at all required in nitrogen or sulfur cycle. Also, symbiotic nitrogen cycle is different than sulfur or carbon cycle as it requires symbiotic association with organisms. This type of association is not required in carbon or sulfur cycle.