Preface

The purpose of this course is to introduce the college-level student to the science of living things on a small scale or the field of microbiology. Microbiology touches on many related topics, including the biochemistry of living things, the different features of cells, pathogens, and the immune system. It is important to understand the biochemistry involved in living structures and to know how organic molecules combine to make living things. Molecular genetics involves the structure and function of DNA and RNA, as well as how they are made and participate in protein synthesis. Pathogens, such as bacteria, viruses, and fungal organisms, cause human diseases and activate the immune system, which is also covered in detail during this course.

Chapter one in the course introduces microbiology by first covering the different types of microorganism you might uncover in your quest to understand the fundamentals of this subject. In the laboratory setting, you may have to learn the different staining techniques involved in the identification of microbes so this is discussed in the chapter. There are different types of microscopy used to study pathogens and other microorganisms, including light microscopy, dark field microscopy, and electron microscopy—each of which is covered as part of the chapter.

Chapter two opens up with a discussion of the origins of cell theory as well as the different historical aspects of how cells are viewed today. The two types of cells are introduced in chapter one and are further expanded upon in this chapter. Features that make prokaryotic cells unique and things that define what results in a cell being called eukaryotic are also covered in this chapter.

Chapter three in the course involves the study of acellular pathogens, which mainly involves viruses. Viruses may or may not be pathogenic and do not have the capability of surviving outside of a cell. There are viruses that can infect all forms of life. The life cycle of viruses is discussed in the chapter along with the ways that viruses are cultured and isolated. There are other acellular pathogens less complex than viruses that are talked about in the chapter, including viroids, virusoids, and prions.

The topic of chapter four is prokaryotic cells. There are features of prokaryotic habitats and their microbiomes you need to know about. In addition, prokaryotes are divided into bacteria and archaea. The different type of bacteria, such as proteobacteria, Gramnegative bacteria, Gram-positive bacteria, and photobacteria are discussed in this chapter. The different features that describe the Archaea domain are also covered as part of the chapter.

While there are many different kinds of eukaryotes, including plant and animal species, chapter five in the course focuses mainly on eukaryotic cells that qualify as microorganisms. These include unicellular pathogens that are also eukaryotic like protists, helminths, and fungi. Algae and lichens are not pathogenic but are still important microbiological organisms covered in this chapter.

Chapter six teaches you the biochemistry you need to know in order to study microbiology. All living things are basically made structurally of organic molecules and the interactions between the molecules is strictly biochemical in nature. For this reason, you need to understand what the different organic molecules are in living things. Nucleic acids are studied in another chapter but carbohydrates, lipids, and proteins are part of this chapter. The way biochemistry helps in understanding microbiology is also covered in the chapter.

Chapter seven in the course talks about cellular metabolism, which is how microbial organisms get their cellular energy. Most of this involves catabolism, which is the breakdown of certain molecules. How cells catabolize carbohydrates, lipids, and proteins is discussed in this chapter. Some organisms derive their energy from the sun. This is called photosynthesis, which is a part of this chapter. Finally, biogeochemical cycles are important to the environment so these are explained in the chapter.

The focus of chapter eight is the genome of the cell. Cellular organisms generally have DNA making up their genome. Both DNA and RNA are nucleic acids, which are important in the genetic functioning of the cell. The structure and function of DNA and RNA are covered as part of the chapter. The totality of the DNA in a cell is referred to as the genome. The different characteristics of a cell’s genome are discussed in this chapter.

Chapter nine in the course expands on the study of DNA by looking into microbial genetics. The ways in which DNA is replicated, the transcription process, and the processes involved in protein synthesis are covered in the chapter. Other things discussed are genetic mutations and the different ways genes are regulated. How each of these things leads to genetic diversity in prokaryotes is also discussed in the chapter.

Chapter ten touches on aspects of laboratory microbiology by looking into microbial growth. The different patterns of microbial binary fission and bacterial growth in cultures is important to understand as a laboratory microbiologist. There are certain factors that increase or decrease microbial growth, which are covered in the chapter, along with the different physical and chemical methods of controlling microbial growth both in culture and in the environment.

Chapter eleven in the course focuses on the different antimicrobial agents used to treat infectious diseases. There are different classifications of antimicrobial agents, some being bacteriostatic and some being bactericidal. There are antibiotics, antifungals, and antivirals, which are covered in this chapter. The public and medical professionals face serious challenges with regard to antibiotic and drug resistances. Some of these challenges are discussed as part of this chapter.

The focuses of chapter twelve are pathogenicity, infectious diseases, and epidemiology of infections. The basic definition of an infectious disease is explained as well as what defines a pathogen. There are specific virulence factors that identify viruses, prokaryotes, and some eukaryotes as being pathogenic in nature, which are discussed. The study of epidemiology as it applies to tracking infectious diseases is also covered in this chapter.

Chapter thirteen in the chapter is about the innate immune system. It starts with physical mechanisms in the host used to prevent infection as well as chemical protective mechanisms. The innate immune system involves a nonspecific host response, including inflammation, which is explained in the chapter. The process of phagocytosis is crucial to the innate immune response; how this works is discussed in the chapter.

The topic of chapter fourteen is the adaptive immune system, which is far more specific against certain pathogens than the innate immune system. There are B cells that are

responsible for making antibodies and T cells that participate in killing infected cells that have been marked with specific antibodies. Both the T cell line and the B cell line have memory cells that retain the memory of a past infection. Vaccines are given to provide immunity to individuals before they get an infection.

Chapter fifteen in the course explains several different advance laboratory techniques used in the laboratory in the making of certain drugs and in the detection of diseases that cannot be identified with cultures. Antibodies are specific to a certain pathogen so there are techniques used to identify infectious diseases, which are generally viral in nature or involve fastidious pathogens for which antibodies have been made in the affected patient. Enzyme-linked immunosorbent assays or ELISA testing and fluorescent antibody testing are two of the techniques discussed in the chapter.