Ch 9: Understanding Viruses
About This Chapter
Understanding Viruses - Chapter Summary
In this chapter, you'll explore the fundamentals of viruses. As you work through these bite-sized and entertaining lessons, you'll see how viruses live, attack, replicate, mutate and affect host cells. You'll also compare different types of viruses. You can complete the chapter at your own pace using any Internet-connected device. To help you retain your knowledge, we've included lesson quizzes and a chapter exam. You can also print lesson transcripts and submit questions to our instructors if you have any. When you're finished, you'll be able to:
- Understand virus structures and functions
- Compare virus shapes
- Summarize the overall life cycle of a virus
- Interpret virus classification in terms of the viral genome and replication scheme
- Compare DNA and RNA virus replication
- Explain virus mutation
- Differentiate between the bacteriophage lytic and lysogenic circles
- Assess virus isolation, detection and identification
- Evaluate concepts pertaining to immune system evasion, flu viruses and HIV
- Describe the effect that viruses can have on host cells
1. What Are Viruses? - Definition, Structure & Function
In this lesson, you'll learn some historical facts about viruses and the material they are composed of. Find out more as we review the capsid, nucleic acids, the viral envelope, viruses, virions, bacteriophages and virology.
2. Shapes of a Virus: Helical, Icosahedral, Prolate, Complex & Enveloped
Learn about the different shapes viruses can have, such as helical, icosahedral, prolate, complex and enveloped. Find out why one shape is particularly useful from an energetic standpoint.
3. The Life Cycle of a Virus: How Viruses Live, Attack & Replicate
Find out how viruses infect and replicate as we explore the important steps of the virus life cycle, including attachment, uncoating, penetration, replication, and release, as well as the lysogenic and lytic cycles.
4. Classification of Viruses: Viral Genome and Replication Scheme
Find out how viruses are classified based on their being double-stranded, single-stranded, positive-sense, negative-sense, or by having something called reverse transcriptase.
5. Replication of DNA Viruses
This lesson will give you a basic overview of how DNA viruses replicate inside of a host cell. We will cover the entry, integration, replication and release of DNA viruses.
6. Replication of RNA Viruses
This lesson will give you a basic overview of how different types of RNA viruses replicate inside of an animal cell. We will cover the essence of being double-stranded and retroviruses, as well as positive-and negative-sense RNA viruses.
7. How Viruses Mutate: Antigenic Drift and Antigenic Shift
This lesson will discuss the major ways by which viruses, notably the flu virus, mutates. We will talk about recombination, reassortment, antigenic drift, antigenic shift, and more!
8. Viruses: Bacteriophage Lytic and Lysogenic Cycles
Viruses are generally not only our enemy but also the enemy of many other organisms. Bacteriophages are viruses that infect specific bacteria. In this lesson, we'll discuss their basic structure and infection cycle.
9. Flu Viruses, HIV and Immune System Evasion
Why is it that our immune systems can protect us from some viruses but not others? We've eradicated smallpox by using vaccines, so why do influenza and HIV remain such dangerous health risks? In this lesson about viruses, we'll explore these questions and learn how influenza and HIV continue to evade the human immune system.
10. Effect of Viruses on Host Cells
In this lesson we'll be exploring how viruses exert their detrimental effects on host cells. We'll go over the cytopathological implications, such as the latent and lytic cycle, as well as oncogenesis.
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Other Chapters
Other chapters within the UExcel Microbiology: Study Guide & Test Prep course
- Early History of Microbiology
- Fundamentals of Microbiology
- Microbiology Laboratory Procedures
- Understanding Genetics & DNA
- Understanding Metabolism
- Bacterial Biology
- Understanding Diseases
- Protozoan Diseases
- Overview of DNA Viruses
- Overview of RNA Viruses
- Overview of Fungal Infections
- Illnesses & Infections of the GI Tract
- Overview of Bacterial STDs
- Understanding Blood-Borne Bacterial Diseases
- Respiratory Bacterial Infections
- Bacterial Skin and Wound Infections
- Immunology Basics
- Structure & Function of the Immune System
- Overview of Antigens
- Disorders of the Immune System
- Serological & Diagnostic Reactions
- Antimicrobial Drugs Overview
- Sterilization & Antiseptic Methods
- Chemical Methods of Microbial Control
- Effectiveness of Antiseptics & Disinfectants
- Microbiology & the Environment
- Food & Industrial Microbiology Overview
- UExcel Microbiology Flashcards
