Podcast
Questions and Answers
Identify the different environments in which some viruses can replicate.
Identify the different environments in which some viruses can replicate.
Bacterial cells, Animal cells, Human cells
Which of the following activities are not characteristics of viruses?
Which of the following activities are not characteristics of viruses?
The cause of viral infections remained unknown for many years longer than other types of infections due to which of the following reasons?
The cause of viral infections remained unknown for many years longer than other types of infections due to which of the following reasons?
Which of the following describes viruses?
Which of the following describes viruses?
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Which term best describes viruses?
Which term best describes viruses?
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Which of the following relate to all viruses?
Which of the following relate to all viruses?
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Many animal viruses will acquire which of the following from the host cell's membrane?
Many animal viruses will acquire which of the following from the host cell's membrane?
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The viral envelope is compositionally different from a non-infected host cell because of the presence of which of the following?
The viral envelope is compositionally different from a non-infected host cell because of the presence of which of the following?
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Which of the following are reliant on the viral capsid?
Which of the following are reliant on the viral capsid?
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Poliovirus and adenovirus have a capsid arranged in a symmetrical polygon structure called a(n)
Poliovirus and adenovirus have a capsid arranged in a symmetrical polygon structure called a(n)
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Viral glycoproteins are present in the host membrane but not in the viral envelope.
Viral glycoproteins are present in the host membrane but not in the viral envelope.
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Which type of capsids are composed of multiple protein types and nonsymmetrical shapes?
Which type of capsids are composed of multiple protein types and nonsymmetrical shapes?
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Why must living cells carry a larger genome than viruses?
Why must living cells carry a larger genome than viruses?
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Which of the following describes bacteriophages?
Which of the following describes bacteriophages?
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In terms of numbers, how many genes can be found in some viruses?
In terms of numbers, how many genes can be found in some viruses?
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What is common to replicase and reverse transcriptase?
What is common to replicase and reverse transcriptase?
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Which are the criteria used in classifying viruses into families?
Which are the criteria used in classifying viruses into families?
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What term is used to describe when a virus initially 'sticks' to the host cell?
What term is used to describe when a virus initially 'sticks' to the host cell?
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Which of the following best explains why viruses have so few genes?
Which of the following best explains why viruses have so few genes?
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Which preformed enzyme is involved in the synthesis of DNA from RNA in retroviruses, such as HIV?
Which preformed enzyme is involved in the synthesis of DNA from RNA in retroviruses, such as HIV?
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What functions do capsid proteins perform for naked viruses?
What functions do capsid proteins perform for naked viruses?
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Which term describes the tissue specificities of animal viruses for certain body cells?
Which term describes the tissue specificities of animal viruses for certain body cells?
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Which of the following viral structures must be specific for adsorption?
Which of the following viral structures must be specific for adsorption?
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The two main processes by which viruses penetrate host cells are engulfment, also known as __
The two main processes by which viruses penetrate host cells are engulfment, also known as __
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The process of penetration occurs when viruses are taken into the cell followed by engulfment in a vesicle called a(n) __
The process of penetration occurs when viruses are taken into the cell followed by engulfment in a vesicle called a(n) __
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Tropisms are tissue specificities of animal viruses for certain body cells, e.g., the hepatitis B virus targets the _____
Tropisms are tissue specificities of animal viruses for certain body cells, e.g., the hepatitis B virus targets the _____
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Identify all the methods that a virus can use to gain entry into an animal cell.
Identify all the methods that a virus can use to gain entry into an animal cell.
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In which way do enveloped viruses leave their host cell?
In which way do enveloped viruses leave their host cell?
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What is a simple translation of cytopathic?
What is a simple translation of cytopathic?
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What is a name given to a disease-causing agent composed only of protein?
What is a name given to a disease-causing agent composed only of protein?
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Using a microscope, you observe some cells which have multiple nuclei because a virus has caused normal cells to fuse together. What is this observation called?
Using a microscope, you observe some cells which have multiple nuclei because a virus has caused normal cells to fuse together. What is this observation called?
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AAV can only replicate in cells infected with?
AAV can only replicate in cells infected with?
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Study Notes
Virus Characteristics and Structure
- Viruses can replicate in various environments including bacterial, animal, and human cells.
- Viruses are considered non-living infectious agents characterized by their ultramicroscopic size.
- They lack the ability to metabolize food, maintain homeostasis, replicate independently, or respond to environmental changes.
- Viral structures include an acellular composition that comprises nucleic acids and a protective capsid.
Viral Genomes and Classification
- Viral genomes generally consist of approximately 9 to several hundred genes.
- Criteria for virus family classification include genetic makeup, structural characteristics, and chemical composition.
Viral Entry and Penetration
- Viruses enter host cells through absorption and employ spike proteins for specific adsorption.
- Two main mechanisms for penetration include endocytosis and direct fusion, facilitating the engulfment of viruses into the cells.
- Enveloped viruses escape host cells by a process known as budding.
Viral Proteins and Enzymes
- Capsid proteins provide protection and facilitate attachment in naked viruses.
- Preformed enzymes like replicase and reverse transcriptase play essential roles in viral replication; the latter synthesizes DNA from RNA in retroviruses.
Virus Host Interactions and Effects
- Tropisms refer to the tissue-specific preferences of viruses, such as the affinity of hepatitis B for liver and salivary cells.
- Cytopathic effects occur when viruses induce the fusion of normal cells, resulting in multinucleate cells.
Unique Viral Agents
- Prions are disease-causing agents composed solely of protein, distinct from conventional viruses.
- AAV (Adeno-Associated Virus) requires co-infection with adenoviruses to replicate.
Viral Structures
- Complex capsids have multiple protein types with non-symmetrical shapes.
- The viral envelope is different from the host cell membrane due to the presence of viral proteins, which includes specific glycoproteins.
Important Viral Concepts
- Viruses possess a capsid vital for adsorption and penetration into host cells, while naked viruses rely significantly on their capsid for these functions.
- The process of viral absorption marks the initial attachment phase, which is crucial for successful infection.
Studying That Suits You
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Description
Test your knowledge of viruses with these flashcards from Biology Chapter 6. Learn about their replication environments and characteristics that differentiate them from living organisms. Perfect for students studying microbiology or preparing for exams.
