Microbiology Exam 1 Study Guide Crazy lady review

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Q1. Describe some of the destructive and beneficial actions of microbes.

Background

Topic: Microbial Roles in the Environment and Human Life

This question tests your understanding of how microbes can both harm and help humans and the environment.

Key Terms:

Pathogen: A microbe that causes disease.
Decomposer: Microbes that break down dead matter.
Symbiosis: Interaction between two different organisms living in close association.

Step-by-Step Guidance

Think about examples where microbes cause harm, such as infectious diseases in humans, animals, or plants.
Consider how microbes can spoil food or damage materials.
Now, list ways microbes are beneficial, such as their role in nutrient cycling, food production (e.g., fermentation), or biotechnology.
Reflect on how microbes are used in medicine (e.g., antibiotics) or environmental cleanup.

Try solving on your own before revealing the answer!

Final Answer:

Destructive actions: Microbes can cause diseases (e.g., tuberculosis, influenza), spoil food, and damage crops. Beneficial actions: Microbes decompose organic matter, recycle nutrients, aid in digestion, produce antibiotics, and are used in food production (e.g., yogurt, cheese). They are also used in bioremediation to clean up pollutants.

Q2. What is bioremediation?

Background

Topic: Environmental Microbiology

This question focuses on the use of microbes to address environmental pollution.

Key Terms:

Bioremediation: The use of living organisms to remove or neutralize pollutants.
Pollutant: A substance that contaminates the environment.

Step-by-Step Guidance

Recall the definition of bioremediation and its purpose.
Think of examples where microbes are used to clean up oil spills or detoxify hazardous waste.
Consider why microbes are effective for this process (e.g., their metabolic diversity).

Try solving on your own before revealing the answer!

Final Answer:

Bioremediation is the use of microorganisms to remove or detoxify pollutants from the environment, such as cleaning up oil spills or breaking down toxic chemicals in soil and water.

Q3. Recognize the system of scientific nomenclature that uses two names: a genus and a specific epithet.

Background

Topic: Taxonomy and Nomenclature

This question tests your knowledge of how organisms are named scientifically.

Key Terms:

Binomial nomenclature: The two-name system for naming organisms.
Genus: The first part of the name, always capitalized.
Specific epithet: The second part, not capitalized.

Step-by-Step Guidance

Recall the rules for writing scientific names (italicized or underlined, genus capitalized, species lowercase).
Think of examples, such as Escherichia coli or Staphylococcus aureus.
Consider why this system is important for scientific communication.

Try solving on your own before revealing the answer!

Final Answer:

The system is called binomial nomenclature. Each organism is given a two-part name: the genus (capitalized) and the specific epithet (lowercase), e.g., Homo sapiens.

Q4. Which groups of microbes are prokaryotes? Which are eukaryotes?

Background

Topic: Classification of Microorganisms

This question asks you to distinguish between prokaryotic and eukaryotic microbes.

Key Terms:

Prokaryote: Organisms without a nucleus (e.g., bacteria, archaea).
Eukaryote: Organisms with a nucleus (e.g., fungi, protozoa, algae).

Step-by-Step Guidance

List the main groups of microbes (bacteria, archaea, fungi, protozoa, algae, viruses).
Identify which groups lack a nucleus and which have one.
Remember that viruses are not classified as prokaryotes or eukaryotes.

Try solving on your own before revealing the answer!

Final Answer:

Prokaryotes: Bacteria and Archaea. Eukaryotes: Fungi, protozoa, algae, and helminths. Viruses are not classified as either.

Q5. What is the difference in photosynthesis and cellular respiration? Classify the organisms accordingly.

Background

Topic: Microbial Metabolism

This question tests your understanding of energy production in cells and which organisms perform each process.

Key Terms and Formulas:

Photosynthesis: Process by which light energy is converted to chemical energy.
Cellular respiration: Process by which cells break down glucose to produce ATP.

Step-by-Step Guidance

Recall the basic equations for photosynthesis and cellular respiration.
Identify which organisms (e.g., plants, algae, cyanobacteria) perform photosynthesis.
Identify which organisms perform cellular respiration (most living things, including microbes).
Think about the relationship between these two processes (one produces oxygen and glucose, the other uses them).

Try solving on your own before revealing the answer!

Final Answer:

Photosynthesis converts light energy to chemical energy (glucose) and is performed by plants, algae, and cyanobacteria. Cellular respiration breaks down glucose to produce ATP and is performed by most organisms, including animals, fungi, and many bacteria.

Q6. What are the three domains? What 4 kingdoms are in the domain Eukarya?

Background

Topic: Taxonomy and Classification

This question tests your knowledge of the highest levels of biological classification.

Key Terms:

Domain: The highest taxonomic rank.
Kingdom: The next level below domain.

Step-by-Step Guidance

Recall the three domains of life.
List the four kingdoms within the domain Eukarya.
Think about examples of organisms in each kingdom.

Try solving on your own before revealing the answer!

Final Answer:

The three domains are Bacteria, Archaea, and Eukarya. The four kingdoms in Eukarya are Protista, Fungi, Plantae, and Animalia.

Q7. Explain the importance of observations made by Hooke and van Leeuwenhoek. What is the Cell Theory?

Background

Topic: History of Microbiology

This question focuses on key historical figures and foundational concepts in cell biology.

Key Terms:

Cell Theory: The concept that all living things are composed of cells.
Robert Hooke: First to observe cells in cork.
Antonie van Leeuwenhoek: First to observe living microbes.

Step-by-Step Guidance

Recall what Hooke observed and why it was significant.
Recall what van Leeuwenhoek observed and how it contributed to microbiology.
Define the Cell Theory and its main points.

Try solving on your own before revealing the answer!

Final Answer:

Hooke observed cells in cork, coining the term "cell." Van Leeuwenhoek was the first to observe living microorganisms. The Cell Theory states that all living things are composed of cells, and cells are the basic unit of life.

Q8. Compare spontaneous generation and biogenesis.

Background

Topic: Origin of Life Theories

This question tests your understanding of historical theories about the origin of life.

Key Terms:

Spontaneous generation: The idea that life can arise from nonliving matter.
Biogenesis: The idea that life arises only from preexisting life.

Step-by-Step Guidance

Define both spontaneous generation and biogenesis.
Think about experiments that disproved spontaneous generation (e.g., Pasteur's swan-neck flask experiment).
Consider the implications of each theory for microbiology.

Try solving on your own before revealing the answer!

Final Answer:

Spontaneous generation proposed that life could arise from nonliving matter, while biogenesis states that life comes only from preexisting life. Pasteur's experiments supported biogenesis.

Q9. Summarize the Germ Theory of disease and know the scientist given credit for his contributing work.

Background

Topic: Microbial Pathogenesis

This question focuses on the theory that microbes cause disease and the scientists involved.

Key Terms:

Germ Theory: The idea that microorganisms cause disease.
Louis Pasteur and Robert Koch: Key contributors.

Step-by-Step Guidance

Define the Germ Theory of disease.
Identify the main scientists who contributed to this theory.
Think about the experiments or postulates that supported this theory.

Try solving on your own before revealing the answer!

Final Answer:

The Germ Theory states that microorganisms are the cause of many diseases. Louis Pasteur and Robert Koch are credited for their work, with Koch developing postulates to link specific microbes to specific diseases.

Q10. What is the importance and significance of Koch’s postulates and Pasteur’s work?

Background

Topic: Foundations of Microbiology

This question asks about the impact of key experiments and principles in microbiology.

Key Terms:

Koch's postulates: Criteria to establish a causative relationship between a microbe and a disease.
Pasteur's work: Disproved spontaneous generation, developed vaccines, and pasteurization.

Step-by-Step Guidance

Recall what Koch's postulates are and why they are important for identifying disease-causing microbes.
Summarize Pasteur's major contributions to microbiology.
Think about how these contributions advanced the field and improved public health.

Try solving on your own before revealing the answer!

Final Answer:

Koch's postulates provided a systematic method to link specific microbes to specific diseases. Pasteur's work disproved spontaneous generation, developed vaccines, and introduced pasteurization, greatly advancing microbiology and public health.

Q11. Identify the contributions to microbiology made by Ehrlich, Jenner, and Fleming. What was Ehrlich’s “magic bullet”?

Background

Topic: History of Microbiology and Chemotherapy

This question focuses on key figures in the development of immunology and antimicrobial therapy.

Key Terms:

Paul Ehrlich: Developed the concept of a "magic bullet" drug.
Edward Jenner: Developed the first vaccine (smallpox).
Alexander Fleming: Discovered penicillin.

Step-by-Step Guidance

Recall the main achievements of each scientist.
Define what Ehrlich meant by a "magic bullet."
Think about how these discoveries impacted medicine and microbiology.

Try solving on your own before revealing the answer!

Final Answer:

Ehrlich developed the first synthetic antimicrobial drug (Salvarsan) and the concept of a "magic bullet" that targets pathogens without harming the host. Jenner developed the smallpox vaccine. Fleming discovered penicillin, the first antibiotic.

Q12. Describe important contributions of Golden Age and Modern Age scientists to Microbiology.

Background

Topic: History of Microbiology

This question asks you to summarize key advances in microbiology from different eras.

Key Terms:

Golden Age: Late 1800s to early 1900s, major discoveries in microbiology.
Modern Age: Recent advances, including molecular biology and genomics.

Step-by-Step Guidance

List major discoveries from the Golden Age (e.g., Germ Theory, vaccines, pure culture techniques).
Identify key advances from the Modern Age (e.g., DNA structure, PCR, genomics).
Think about how these advances have shaped current microbiology.

Try solving on your own before revealing the answer!

Final Answer:

Golden Age scientists established the Germ Theory, developed vaccines, and pure culture techniques. Modern Age scientists discovered DNA structure, developed PCR, and advanced genomics, transforming microbiology into a molecular science.

Q13. Define bacteriology, mycology, parasitology, immunology, and virology.

Background

Topic: Branches of Microbiology

This question tests your knowledge of the different fields within microbiology.

Key Terms:

Bacteriology: Study of bacteria.
Mycology: Study of fungi.
Parasitology: Study of parasites.
Immunology: Study of the immune system.
Virology: Study of viruses.

Step-by-Step Guidance

Define each branch based on the type of organism or system studied.
Think of examples of what each branch might investigate.

Try solving on your own before revealing the answer!

Final Answer:

Bacteriology: Study of bacteria. Mycology: Study of fungi. Parasitology: Study of parasites. Immunology: Study of the immune system. Virology: Study of viruses.

Q14. Differentiate normal and transient microbiota as they pertain to infectious disease. (Human microbiome)

Background

Topic: Human Microbiome

This question focuses on the types of microbes found on and in the human body.

Key Terms:

Normal microbiota: Microbes that are permanently present in the body.
Transient microbiota: Microbes that are present temporarily.

Step-by-Step Guidance

Define normal and transient microbiota.
Consider how each type interacts with the host and their role in health and disease.
Think about examples of each and their significance in infectious disease.

Try solving on your own before revealing the answer!

Final Answer:

Normal microbiota are permanently present and usually beneficial, while transient microbiota are temporary and may cause disease if they persist or invade tissues. Both play roles in health and disease.

Q15. What are opportunists and how do they function in the causation of disease? Define biofilm.

Background

Topic: Pathogenicity and Microbial Communities

This question tests your understanding of how certain microbes cause disease and what biofilms are.

Key Terms:

Opportunistic pathogen: A microbe that causes disease only when the host's defenses are compromised.
Biofilm: A community of microbes attached to a surface and embedded in a self-produced matrix.

Step-by-Step Guidance

Define opportunists and describe when they cause disease.
Explain what a biofilm is and why it is important in microbiology.
Think about examples of diseases caused by opportunists and biofilms.

Try solving on your own before revealing the answer!

Final Answer:

Opportunists are microbes that cause disease when the host's immune system is weakened. A biofilm is a structured community of microbes attached to a surface, often resistant to antibiotics and immune responses.

Q16. What is the difference in active and passive types of molecular movement across membranes?

Background

Topic: Cell Membrane Transport

This question tests your understanding of how substances move across cell membranes.

Key Terms:

Active transport: Movement of molecules against a concentration gradient, requiring energy.
Passive transport: Movement of molecules down a concentration gradient, no energy required.

Step-by-Step Guidance

Define active and passive transport.
List examples of each type (e.g., diffusion, facilitated diffusion, osmosis for passive; pumps for active).
Consider the role of energy (ATP) in active transport.

Try solving on your own before revealing the answer!

Final Answer:

Active transport requires energy to move substances against a concentration gradient, while passive transport does not require energy and moves substances down their gradient.

Q17. What is the difference in the terms hydrophilic and hydrophobic?

Background

Topic: Chemistry of Life

This question tests your understanding of molecular properties related to water.

Key Terms:

Hydrophilic: Water-loving, dissolves in water.
Hydrophobic: Water-fearing, does not dissolve in water.

Step-by-Step Guidance

Define hydrophilic and hydrophobic.
Think about examples of each (e.g., salts, sugars for hydrophilic; oils, fats for hydrophobic).
Consider how these properties affect cell membrane structure.

Try solving on your own before revealing the answer!

Final Answer:

Hydrophilic substances are attracted to water and dissolve in it, while hydrophobic substances repel water and do not dissolve in it.

Q18. Know definition and importance of Prokaryotic and Eukaryotic structures discussed in exam chapters. Table 3.6

Background

Topic: Cell Structure

This question asks you to recall the key differences between prokaryotic and eukaryotic cell structures.

Key Terms:

Prokaryotic cell: Lacks a nucleus and membrane-bound organelles.
Eukaryotic cell: Has a nucleus and membrane-bound organelles.

Step-by-Step Guidance

List the main structures found in prokaryotic cells (e.g., cell wall, plasma membrane, ribosomes, nucleoid).
List the main structures found in eukaryotic cells (e.g., nucleus, mitochondria, endoplasmic reticulum).
Consider the functional significance of these structures.

Try solving on your own before revealing the answer!

Final Answer:

Prokaryotic cells lack a nucleus and membrane-bound organelles, while eukaryotic cells have both. These structural differences affect cellular processes and complexity.

Q19. Know and discuss Cell Wall and Cell Membrane structure/function and how it contributes to Gram Stain reactions.

Background

Topic: Bacterial Cell Structure and Staining

This question tests your understanding of bacterial cell walls, membranes, and the Gram stain technique.

Key Terms:

Cell wall: Provides shape and protection; composition differs in Gram-positive and Gram-negative bacteria.
Cell membrane: Controls movement of substances in and out of the cell.
Gram stain: Differentiates bacteria based on cell wall structure.

Step-by-Step Guidance

Describe the structure and function of the cell wall and cell membrane.
Explain the differences between Gram-positive and Gram-negative cell walls.
Relate these differences to the results of the Gram stain.

Try solving on your own before revealing the answer!

Final Answer:

Gram-positive bacteria have thick peptidoglycan cell walls that retain crystal violet stain, appearing purple. Gram-negative bacteria have thin peptidoglycan and an outer membrane, losing the stain and appearing pink. The cell wall structure determines the Gram stain result.

Q20. Know identifying characteristics of specific organisms discussed in class.

Background

Topic: Microbial Identification

This question asks you to recall distinguishing features of microbes covered in your course.

Key Terms:

Identification: Determining the identity of a microbe based on characteristics.

Step-by-Step Guidance

List the key characteristics used to identify microbes (e.g., shape, staining, metabolism, genetic tests).
Recall specific examples discussed in your class notes or textbook.
Consider how these characteristics help differentiate between species.

Try solving on your own before revealing the answer!

Final Answer:

Identifying characteristics include cell shape, Gram reaction, metabolic properties, and genetic markers. Specific examples depend on your class content (e.g., Staphylococcus aureus: Gram-positive cocci, catalase positive).

Q21. Know physical and chemical requirements for nutrition and growth of microorganisms.

Background

Topic: Microbial Nutrition and Growth

This question tests your understanding of what microbes need to grow.

Key Terms:

Physical requirements: Temperature, pH, osmotic pressure.
Chemical requirements: Carbon, nitrogen, sulfur, phosphorus, trace elements, oxygen.

Step-by-Step Guidance

List the main physical factors affecting microbial growth.
List the main chemical nutrients required by microbes.
Consider how these requirements vary among different microbes.

Try solving on your own before revealing the answer!

Final Answer:

Microbes require specific temperatures, pH, and osmotic conditions, as well as nutrients like carbon, nitrogen, sulfur, phosphorus, and trace elements. Oxygen requirements vary among species.

Q22. Know and discuss population growth of microbes and growth curves.

Background

Topic: Microbial Growth

This question focuses on how microbial populations increase and the phases of growth.

Key Terms and Formulas:

Growth curve: Lag, log, stationary, and death phases.
Binary fission: Main method of bacterial reproduction.

Step-by-Step Guidance

Describe the four phases of a typical bacterial growth curve.
Explain what happens in each phase.
Consider how environmental factors affect the growth curve.

Try solving on your own before revealing the answer!

Final Answer:

The microbial growth curve includes lag (adaptation), log (exponential growth), stationary (nutrient depletion), and death (decline) phases. Growth is usually by binary fission.

Q23. Give a complete definition of a virus. Know each of the morphologies and give examples.

Background

Topic: Virology

This question tests your understanding of what viruses are and their structural diversity.

Key Terms:

Virus: Acellular infectious agent with DNA or RNA.
Capsid: Protein coat.
Envelope: Lipid membrane in some viruses.

Step-by-Step Guidance

Define a virus and its basic components.
List the main viral morphologies (e.g., helical, icosahedral, complex, enveloped).
Give examples of viruses with each morphology.

Try solving on your own before revealing the answer!

Final Answer:

A virus is a nonliving, acellular infectious agent with DNA or RNA, a protein coat (capsid), and sometimes an envelope. Morphologies include helical (e.g., tobacco mosaic virus), icosahedral (e.g., adenovirus), complex (e.g., bacteriophage), and enveloped (e.g., influenza virus).

Q24. Differentiate a virus from a bacterium. (Know viral definition, size, structures). Define viral species.

Background

Topic: Virology vs. Bacteriology

This question asks you to compare viruses and bacteria and define what constitutes a viral species.

Key Terms:

Virus: Acellular, requires host, smaller than bacteria.
Bacterium: Cellular, can reproduce independently.
Viral species: Group of viruses sharing genetic information and ecological niche.

Step-by-Step Guidance

List the main differences between viruses and bacteria (structure, size, replication).
Define what is meant by a viral species.
Consider examples to illustrate the differences.

Try solving on your own before revealing the answer!

Final Answer:

Viruses are acellular, much smaller than bacteria, and require a host to replicate. Bacteria are cellular and can reproduce independently. A viral species is a group of viruses with similar genetic material and ecological niche.

Q25. How are bacteriophage cultured? Describe the lytic vs lysogenic cycles of replication.

Background

Topic: Bacteriophage Biology

This question tests your understanding of how bacteriophages are grown and their replication cycles.

Key Terms:

Bacteriophage: Virus that infects bacteria.
Lytic cycle: Virus replicates and lyses host cell.
Lysogenic cycle: Viral DNA integrates into host genome.

Step-by-Step Guidance

Describe how bacteriophages are cultured using bacterial lawns and plaques.
Outline the steps of the lytic cycle.
Outline the steps of the lysogenic cycle.
Compare the outcomes of each cycle for the host cell.

Try solving on your own before revealing the answer!

Final Answer:

Bacteriophages are cultured on bacterial lawns, forming plaques. The lytic cycle results in host cell lysis and virus release, while the lysogenic cycle involves integration of viral DNA into the host genome, with no immediate lysis.

Q26. What is cell culture and how does it apply to virology?

Background

Topic: Virology Techniques

This question focuses on how viruses are grown in the lab.

Key Terms:

Cell culture: Growing cells in controlled conditions outside the organism.
Virology: Study of viruses.

Step-by-Step Guidance

Define cell culture and its purpose.
Explain why cell culture is necessary for studying viruses.
Describe how viruses are propagated in cell cultures.

Try solving on your own before revealing the answer!

Final Answer:

Cell culture involves growing cells in the lab, providing a host for viruses to replicate. It is essential for isolating, studying, and producing viruses for research and vaccine development.

Q27. Compare bacteriophage to animal virus replication. What is cytopathic effect?

Background

Topic: Viral Replication

This question asks you to compare how bacteriophages and animal viruses replicate and define cytopathic effect.

Key Terms:

Bacteriophage: Virus infecting bacteria.
Animal virus: Virus infecting animal cells.
Cytopathic effect: Visible changes in host cells due to viral infection.

Step-by-Step Guidance

List the main steps in bacteriophage replication (attachment, penetration, biosynthesis, maturation, release).
List the main steps in animal virus replication (entry, uncoating, biosynthesis, assembly, release).
Define cytopathic effect and give examples.

Try solving on your own before revealing the answer!

Final Answer:

Bacteriophage replication involves injection of DNA, while animal viruses enter by endocytosis or fusion. Cytopathic effect refers to structural changes in host cells caused by viral infection, such as cell lysis or syncytia formation.

Q28. Give examples of Oncogenic viruses. What is the Oncogenic Theory?

Background

Topic: Viruses and Cancer

This question tests your knowledge of viruses that can cause cancer and the theory behind it.

Key Terms:

Oncogenic virus: Virus that can cause cancer.
Oncogenic Theory: The idea that certain viruses can induce cancer.

Step-by-Step Guidance

List examples of oncogenic viruses (e.g., HPV, EBV, HBV).
Define the Oncogenic Theory.
Consider how these viruses cause cancer (e.g., integration into host DNA).

Try solving on your own before revealing the answer!

Final Answer:

Examples of oncogenic viruses include human papillomavirus (HPV), Epstein-Barr virus (EBV), and hepatitis B virus (HBV). The Oncogenic Theory states that certain viruses can cause cancer by altering host cell DNA.

Q29. Describe the multiplication cycle of a retrovirus—what is the enzyme used—give an example.

Background

Topic: Retroviruses

This question focuses on how retroviruses replicate and the key enzyme involved.

Key Terms:

Retrovirus: RNA virus that uses reverse transcription.
Reverse transcriptase: Enzyme that converts RNA to DNA.

Step-by-Step Guidance

Outline the steps of retrovirus replication (entry, reverse transcription, integration, transcription, assembly, release).
Identify the enzyme responsible for reverse transcription.
Give an example of a retrovirus (e.g., HIV).

Try solving on your own before revealing the answer!

Final Answer:

Retroviruses enter the host cell, use reverse transcriptase to convert RNA to DNA, integrate into the host genome, and produce new viruses. HIV is a well-known retrovirus.

Q30. Know terminology: virus, virion, viroid, prion, plaques, prophage, diseases of DNA or RNA viruses

Background

Topic: Virology Terminology

This question tests your knowledge of key terms in virology.

Key Terms:

Virus: Infectious agent with DNA or RNA.
Virion: Complete, infectious virus particle.
Viroid: Infectious RNA molecule, no protein coat.
Prion: Infectious protein.
Plaque: Clear area on a bacterial lawn due to virus lysis.
Prophage: Phage DNA integrated into bacterial genome.

Step-by-Step Guidance

Define each term listed.
Give examples where appropriate (e.g., prion diseases, DNA/RNA virus diseases).
Consider how these terms relate to viral structure and replication.

Try solving on your own before revealing the answer!

Final Answer:

Virus: Infectious agent with nucleic acid and protein coat. Virion: Complete virus particle. Viroid: Infectious RNA, no protein. Prion: Infectious protein. Plaques: Clear zones from virus lysis. Prophage: Phage DNA in bacterial genome. DNA virus diseases: herpes, smallpox; RNA virus diseases: influenza, HIV.

Q31. Compare the structure/replication of an enveloped and a nonenveloped virus.

Background

Topic: Viral Structure and Replication

This question asks you to compare how enveloped and nonenveloped viruses differ in structure and replication.

Key Terms:

Enveloped virus: Has a lipid membrane.
Nonenveloped virus: Lacks a lipid membrane.

Step-by-Step Guidance

Describe the structural differences between enveloped and nonenveloped viruses.
Explain how each type enters and exits host cells.
Consider examples of each type.

Try solving on your own before revealing the answer!

Final Answer:

Enveloped viruses have a lipid membrane and often enter/exit cells by fusion or budding. Nonenveloped viruses lack this membrane and typically enter by endocytosis and exit by cell lysis. Examples: Influenza (enveloped), poliovirus (nonenveloped).

Q32. Give reasons supporting viruses as non-living entities.

Background

Topic: Nature of Viruses

This question tests your understanding of why viruses are considered non-living.

Key Terms:

Living vs. non-living: Criteria for life.

Step-by-Step Guidance

List the characteristics of living things (e.g., metabolism, reproduction, response to stimuli).
Compare these to the properties of viruses.
Identify which criteria viruses do not meet.

Try solving on your own before revealing the answer!

Final Answer:

Viruses are considered non-living because they cannot reproduce or carry out metabolism independently; they require a host cell for replication and lack cellular structure.