Microbiology: The Science

Microbiology: The Science

• Microbiology is the study of microbes, which can be observed only with the use of various types of microscopes.
• Microbes are collectively referred to as microorganisms, which include acellular microbes (infectious particles) and cellular microbes (microorganisms).
• Acellular microbes include viruses and prions.
• Cellular microbes include all bacteria, all archaea, some algae, all protozoa, and some fungi.

Importance of Microbes

• Microbes are essential for life on Earth as we know it.
• They are involved in the decomposition of dead organisms and waste products of living organisms, making them decomposers or saprophytes.
• Microbes are capable of decomposing industrial wastes, such as oil spills, and are used in bioremediation.
• They are involved in elemental cycles, such as the carbon, nitrogen, oxygen, sulfur, and phosphorous cycles.
• Microbes are essential in various food and beverage industries, such as the production of antibiotics, enzymes, and chemicals.

Microbial Ecology

• Microbial ecology is the study of the relationships between microbes and the environment.
• Microbes are involved in the nitrogen cycle, where certain bacteria convert nitrogen gas in the air to ammonia in the soil.
• Algae and bacteria serve as food for tiny animals, which are then eaten by larger animals, forming the base of many food chains.

Microbes and Disease

• Microbes cause two categories of diseases: infectious diseases and microbial intoxications.
• Infectious diseases are caused by pathogens that colonize the host body and cause disease.
• Microbial intoxications are caused by toxins produced by pathogens that are ingested by a person.
• Only about 3% of known microbes are capable of causing disease.

History of Microbiology

• The first microbes on Earth were likely archaea and cyanobacteria.
• Earliest known infectious diseases include tuberculosis, syphilis, parasitic worm infections, tapeworm infections, pestilence (plague), and smallpox.
• The study of microbes has led to many important discoveries and applications, including the development of antibiotics, vaccines, and genetic engineering.

Key Terms

• Microbes: collectively referred to as microorganisms, including acellular microbes (infectious particles) and cellular microbes (microorganisms).

• Ubiquitous: meaning that microbes are virtually everywhere.

• Indigenous microflora: the microbes that usually live on or in a person.

• Opportunistic pathogen: a microbe that does not cause disease under ordinary conditions but has the potential to cause disease should the opportunity present itself.

• Saprophyte: an organism that lives on dead or decaying organic matter.### AL Activity: CAT 3-2-1

• This activity is an exit ticket to be completed at the end of the class period.

• It consists of three parts: recording three things learned from the lesson, two things found interesting, and one question still unanswered.

Three Things Learned

• Requires recording three key takeaways from the lesson.

Two Things to Learn More About

• Involves identifying two topics that sparked interest and warrant further exploration.

One Question Remaining

• Encourages students to articulate one question they still have about the lesson, promoting critical thinking and curiosity.