1 .		1.2 Concept Check The cell has a barrier, the cytoplasmic membrane, that separates the cytoplasm from the environment. Other cell features include the nucleus or nucleoid, cell wall, and cytoplasm. Certain key features, such as metabolism and reproduction, are associated with the living state, and cells can be thought of conceptually as both chemical machines and as biological coding devices. List the six features associated with living organisms. Why is each feature important to the survival of a cell? Compare the machine and coding functions of a microbial cell. Why is neither of value to a cell without the other? Name the four classes of cellular macromolecules.   To create paragraphs in your essay response, type <p> at the beginning of the paragraph, and </p> at the end.
2 .		1.3 Concept Check Microorganisms exist in nature in populations that interact with other populations in microbial communities. The activities of microbial communities can greatly affect the chemical and physical properties of their habitats. Most of the biomass on Earth is microbial. What is a microbial habitat? How do microorganisms change the chemical and physical properties of their habitats? Where are most prokaryotic cells located on Earth?   To create paragraphs in your essay response, type <p> at the beginning of the paragraph, and </p> at the end.
3 .		1.4 Concept Check Microorganisms can be both beneficial and harmful to humans. Although we tend to emphasize harmful microorganisms (infectious disease agents), many more microorganisms in nature are beneficial than harmful. In what ways are microorganisms important in the food and agriculture industries? What fuels can be made by microorganisms? What is biotechnology, and how might it improve the lives of humans?   To create paragraphs in your essay response, type <p> at the beginning of the paragraph, and </p> at the end.
4 .		1.5 Concept Check Ferdinand Cohn founded the field of bacteriology and discovered bacterial endospores. Louis Pasteur’s work on spontaneous generation led to the development of methods for control of the growth of microorganisms. Robert Koch developed criteria for the study of infectious microorganisms and developed the first methods for the growth of pure cultures and microorganisms. How did Pasteur’s famous experiment defeat the theory of spontaneous generation? How can Koch’s postulates prove cause and effect in a disease? What advantages do solid media offer for the culture of microorganisms?   To create paragraphs in your essay response, type <p> at the beginning of the paragraph, and </p> at the end.
5 .		1.6 Concept Check Unlike Koch and Pastuer, Beijerinck and Winogradsky studied bacteria in soil and water and developed the enrichment culture technique for the specific isolation of representatives of specific physiological groups. In the middle to latter part of the twentieth century, basic and applied microbiology worked hand in hand to usher in the current era of molecular microbiology. What is the enrichment culture technique, and why was it a useful new method in microbiology? List the subdisciplines of microbiology whose focus is the following: metabolism, enzymology, nucleic acid and protein synthesis, microorganisms and their natural environments.   To create paragraphs in your essay response, type <p> at the beginning of the paragraph, and </p> at the end.