CHAPTER 1 STUDY GUIDE 2 PDF

1. Describe the Linnaean naming and classification system of microorganisms using scientific nomenclature. The Linnaean system is a method of classifying and naming organisms that was developed by Carl Linnaeus in the 18th century. It is based on a hierarchical structure and uses...

1. Describe the Linnaean naming and classification system of microorganisms using scientific nomenclature. The Linnaean system is a method of classifying and naming organisms that was developed by Carl Linnaeus in the 18th century. It is based on a hierarchical structure and uses binomial nomenclature, meaning each organism is given a two-part Latin name: o Genus: The first part of the name, which is capitalized. It groups organisms that are closely related. Example: Escherichia*(for Escherichia coli). o Species: The second part of the name, which is lowercase. It refers to the specific organism within the genus. Example: coli (in Escherichia coli). Together, the genus and species form the organism's full scientific name, such as Escherichia coli (E. coli). The name should always be italicized or underlined. This system allows scientists around the world to identify and classify organisms consistently. In addition to the Genus and species, organisms are also classified into broader categories in a hierarchy that includes: o Domain o Kingdom o Phylum o Class o Order o Family o Genus o Species This classification helps us understand evolutionary relationships and how organisms are related to one another. 2. Describe different ways microbes impact our lives and the planet. Microbes have profound effects on both our lives and the planet, both positively and negatively. Here are some key examples: a) Human health: o Beneficial microbes, such as Lactobacillus in the gut, aid in digestion and produce vitamins (e.g., vitamin K). The human microbiome plays a crucial role in maintaining health by outcompeting harmful pathogens and supporting the immune system. o Pathogenic microbes: Some microbes cause diseases, such as bacteria like Streptococcus pneumoniae causing pneumonia, or viruses—such as the flu virus or COVID-19—which can lead to outbreaks, epidemics, or pandemics. b) Food industry: o Microbes such as yeast (for bread, beer, and wine) and bacteria (for yogurt, and cheese) are used in the production of many foods. o Fermentation by microorganisms plays a crucial role in food preservation and flavor development. c) Environmental impact: o Decomposition: Microorganisms decompose dead organisms, recycling nutrients into the soil and maintaining the balance of ecosystems. o Nitrogen fixation: Some bacteria convert nitrogen from the air into a form plants can use, which is essential for plant growth and agriculture. o Bioremediation: Certain bacteria are used to clean up environmental pollutants, like oil spills, by breaking down harmful substances.  d) Biotechnology and Medicine: o Production of medicines: Microbes are used to produce antibiotics (e.g., penicillin from fungi), vaccines, and insulin. o Genetic engineering: Microbes are tools in biotechnology, such as using Escherichia coli to produce human insulin through recombinant DNA technology. 3. Provide examples of how microbes are beneficial. Microorganisms are beneficial in various ways: a. Gut health: o Probiotics such as Lactobacillus and Bifidobacterium aid digestion and nutrient absorption. Additionally, they safeguard the gut by competing with harmful pathogens. b. Food production: o Saccharomyces cerevisiae (yeast) is used to ferment sugars into alcohol and carbon dioxide, which is essential for making bread, beer, and wine. o Lactobacillus is used to ferment dairy products, producing yogurt and cheese. c. Antibiotic production: o Fungi such as Penicillium produce antibiotics (e.g., penicillin), which are crucial for treating bacterial infections. d. Environmental cleanup: o Certain bacteria are used in bioremediation to degrade pollutants, such as Pseudomonas to break down oil spills or heavy metals. o Nitrogen fixation: bacteria live in plant root nodules and convert atmospheric nitrogen into ammonia, which plants use for growth. This is essential for maintaining soil fertility in agriculture. e. Wastewater treatment: Microbes aid in breaking down organic matter in sewage and converting it into less harmful substances during the wastewater treatment process. 4. Define pathogen and infectious disease; describe how pathogens can cause infectious disease. Pathogen: A pathogen is a microorganism (such as a virus, bacterium, fungus, or parasite) that causes disease in a host organism. Pathogens include a variety of organisms like bacteria (Mycobacterium tuberculosis), viruses (HIV), fungi (Candida), and protozoa (Plasmodium). Infectious disease: This is a condition caused by pathogens invading and multiplying in the body. Such diseases can spread directly or indirectly between individuals or through vectors such as mosquitoes. How pathogens cause infectious disease: a. Entry into the host: Pathogens can enter the body through various routes, such as the skin, respiratory tract, or digestive system. b. Colonization: Once inside, the pathogen may multiply at the site of entry or spread to other areas of the body. c. Evading the immune system: Pathogens often have strategies to evade the host's immune response, such as hiding inside host cells (like viruses) or producing toxins (like Clostridium botulinum). 5. Damage to host tissues: Pathogens cause harm by producing toxins, and enzymes that destroy tissue, or triggering an excessive immune response that damages the host's cells. For example, Staphylococcus aureus produces toxins that lead to tissue destruction and infection. 6. Spread of infection: Pathogens can spread from one host to another through contact, droplets (coughing/sneezing), bodily fluids, contaminated water, or vectors like insects. Examples of infectious diseases include the flu (caused by the influenza virus), tuberculosis (caused by Mycobacterium tuberculosis), and malaria (caused by the protozoan Plasmodium).