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Antiviral drugs typically target:- a)Viral proteins
- b)Host cell proteins
- c)Viral envelopes
- d)Host cell membranes
Correct answer is option 'A'. Can you explain this answer?
Antiviral drugs typically target:
a)
Viral proteins
b)
Host cell proteins
c)
Viral envelopes
d)
Host cell membranes
|
Hazel Hill answered |
Target of Antiviral Drugs: Viral Proteins
Antiviral drugs typically target viral proteins to inhibit viral replication and treat viral infections. Here's how these drugs work:
1. Viral Replication
- Viruses rely on host cells to replicate and spread. They use their own viral proteins to hijack the host cell machinery.
- Antiviral drugs target specific viral proteins involved in crucial steps of the viral replication cycle, such as viral entry, genome replication, protein synthesis, and assembly of new viral particles.
2. Mechanism of Action
- Antiviral drugs can target different viral proteins, depending on the type of virus being treated. For example, drugs targeting the HIV protease enzyme prevent the virus from maturing and infecting new cells.
- By inhibiting viral proteins, these drugs disrupt the viral life cycle and reduce the viral load in the body, ultimately helping the immune system fight off the infection.
3. Specificity
- Targeting viral proteins allows antiviral drugs to be more specific in their action, as they are designed to interfere with viral processes without affecting normal host cell functions.
- This specificity helps to minimize side effects and improve the overall safety profile of antiviral medications.
In conclusion, antiviral drugs are designed to target viral proteins to disrupt viral replication and treat viral infections effectively. By focusing on specific viral targets, these drugs help to combat viral diseases while minimizing harm to the host cells.
Antiviral drugs typically target viral proteins to inhibit viral replication and treat viral infections. Here's how these drugs work:
1. Viral Replication
- Viruses rely on host cells to replicate and spread. They use their own viral proteins to hijack the host cell machinery.
- Antiviral drugs target specific viral proteins involved in crucial steps of the viral replication cycle, such as viral entry, genome replication, protein synthesis, and assembly of new viral particles.
2. Mechanism of Action
- Antiviral drugs can target different viral proteins, depending on the type of virus being treated. For example, drugs targeting the HIV protease enzyme prevent the virus from maturing and infecting new cells.
- By inhibiting viral proteins, these drugs disrupt the viral life cycle and reduce the viral load in the body, ultimately helping the immune system fight off the infection.
3. Specificity
- Targeting viral proteins allows antiviral drugs to be more specific in their action, as they are designed to interfere with viral processes without affecting normal host cell functions.
- This specificity helps to minimize side effects and improve the overall safety profile of antiviral medications.
In conclusion, antiviral drugs are designed to target viral proteins to disrupt viral replication and treat viral infections effectively. By focusing on specific viral targets, these drugs help to combat viral diseases while minimizing harm to the host cells.
Which of the following infection causes a change in the properties of the cell?- a)Latent
- b)Abortive
- c)Transforming
- d)Null
Correct answer is option 'C'. Can you explain this answer?
Which of the following infection causes a change in the properties of the cell?
a)
Latent
b)
Abortive
c)
Transforming
d)
Null
|
Alexander Blake answered |
Transforming Infection
Transforming infection causes a change in the properties of the cell.
- Definition: Transforming infections are caused by viruses that have the ability to transform normal cells into cancerous cells.
- Mechanism: These viruses can integrate their genetic material into the host cell's DNA, disrupting normal cellular processes and leading to uncontrolled cell growth.
- Consequences: The transformed cells can acquire properties such as unlimited growth potential, resistance to cell death, and the ability to invade surrounding tissues, characteristics typical of cancer cells.
- Examples: Some well-known viruses that can cause transforming infections include human papillomavirus (HPV) and Epstein-Barr virus (EBV).
UL37x1 is a protein encoded by __________- a)Cytomegalovirus
- b)HSV
- c)SV40
- d)HIV
Correct answer is option 'A'. Can you explain this answer?
UL37x1 is a protein encoded by __________
a)
Cytomegalovirus
b)
HSV
c)
SV40
d)
HIV
|
Orion Classes answered |
UL37x1 is a protein encoded by human cytomegalovirus which is a herpes virus. The protein inhibits the apoptosis of infected cells, which permits the virus to establish a long-lasting infection.
In which of the following infection the cells do not have the appropriate receptor for the virus?- a)Null
- b)Transforming
- c)Abortive
- d)Cytopathogenic
Correct answer is option 'A'. Can you explain this answer?
In which of the following infection the cells do not have the appropriate receptor for the virus?
a)
Null
b)
Transforming
c)
Abortive
d)
Cytopathogenic
|
|
Orion Classes answered |
Null infection represents the cells which do not have appropriate receptors for a particular virus, and thus cannot interact with virus particle. The viral genome is artificially introduced into such cells in the laboratory to produce progenies.
Which of the following infection results in the continuous production of viruses?- a)Persistent
- b)Abortive
- c)Null
- d)Transforming
Correct answer is option 'A'. Can you explain this answer?
Which of the following infection results in the continuous production of viruses?
a)
Persistent
b)
Abortive
c)
Null
d)
Transforming
|
|
Orion Classes answered |
Persistent infections are the infections that cause or result in the continuous production of infectious viruses. This is achieved either by the survival of the infected cells or by a situation in which a minority of cells are initially infected and the spread of the virus is limited.
The process by which a virus integrates its genetic material into the host cell's genome is called:- a)Lysis
- b)Budding
- c)Lysogeny
- d)Replication
Correct answer is option 'C'. Can you explain this answer?
The process by which a virus integrates its genetic material into the host cell's genome is called:
a)
Lysis
b)
Budding
c)
Lysogeny
d)
Replication
|
|
Orion Classes answered |
Lysogeny is the process in which a virus integrates its genetic material, specifically its DNA, into the host cell's genome. The viral DNA, known as a prophage, becomes a permanent part of the host cell's DNA and can be replicated along with the host cell's genome.
In which of the following infection no infectious progeny is produced?- a)Latent
- b)Abortive
- c)Persistent
- d)Null
Correct answer is option 'A'. Can you explain this answer?
In which of the following infection no infectious progeny is produced?
a)
Latent
b)
Abortive
c)
Persistent
d)
Null
|
|
Orion Classes answered |
The term latent is defined as existing but not exhibited. In terms of the virus-infected cell, it means that the viral genome is present but no infectious progeny is produced. Adeno-associated virus, herpesvirus exhibits latency.
Which infection causes a reduction in the total yield of virus particles?- a)Null
- b)Transforming
- c)Abortive
- d)Cytopathogenic
Correct answer is option 'C'. Can you explain this answer?
Which infection causes a reduction in the total yield of virus particles?
a)
Null
b)
Transforming
c)
Abortive
d)
Cytopathogenic
|
|
Orion Classes answered |
Abortive infection causes a reduction in the total yield of virus particles (sometimes to zero). The quality of the progeny, if produced, maybe deficient as the cells do not replicate that virus with equal efficiency.
The protein coat of a virus is primarily responsible for:- a)Protecting the viral genome
- b)Facilitating viral attachment to host cells
- c)Replicating the viral genome
- d)Assisting in viral protein synthesis
Correct answer is option 'A'. Can you explain this answer?
The protein coat of a virus is primarily responsible for:
a)
Protecting the viral genome
b)
Facilitating viral attachment to host cells
c)
Replicating the viral genome
d)
Assisting in viral protein synthesis
|
|
Orion Classes answered |
The protein coat, or capsid, of a virus serves as a protective layer around the viral genome. It helps shield the genetic material from damage, such as enzymatic degradation, while the virus is outside the host cell.
The envelope of a virus is derived from:- a)The host cell's plasma membrane
- b)The host cell's cytoplasm
- c)The viral capsid
- d)The viral genome
Correct answer is option 'A'. Can you explain this answer?
The envelope of a virus is derived from:
a)
The host cell's plasma membrane
b)
The host cell's cytoplasm
c)
The viral capsid
d)
The viral genome
|
|
Orion Classes answered |
The envelope of a virus is derived from the host cell's plasma membrane or an internal membrane, such as the endoplasmic reticulum or Golgi apparatus. As the virus exits the host cell during the budding process, it acquires a portion of the host's membrane, which becomes part of its envelope.
Which of the following is NOT a component of a typical virus?- a)Protein coat (capsid)
- b)Nucleic acid(DNA or RNA)
- c)Lipid membrane (envelope)
- d)Ribosomes
Correct answer is option 'D'. Can you explain this answer?
Which of the following is NOT a component of a typical virus?
a)
Protein coat (capsid)
b)
Nucleic acid(DNA or RNA)
c)
Lipid membrane (envelope)
d)
Ribosomes
|
|
Orion Classes answered |
Viruses are acellular particles composed of a protein coat called a capsid and a nucleic acid core (DNA or RNA). Some viruses may also possess a lipid membrane called an envelope. However, viruses do not contain ribosomes, which are cellular organelles involved in protein synthesis.
The immune response to a viral infection primarily targets:- a)Viral proteins on the cell surface
- b)Viral RNA or DNA in the host cell
- c)Viral capsids within the host cell
- d)Viral envelopes released from the host cell
Correct answer is option 'B'. Can you explain this answer?
The immune response to a viral infection primarily targets:
a)
Viral proteins on the cell surface
b)
Viral RNA or DNA in the host cell
c)
Viral capsids within the host cell
d)
Viral envelopes released from the host cell
|
|
Orion Classes answered |
The immune response primarily targets viral RNA or DNA within the host cell. Immune cells recognize and respond to viral genetic material as a sign of infection, triggering a cascade of immune responses to eliminate the infected cells and control the spread of the virus.
Which of the following infection is also called as lytic infection?- a)Null
- b)Cytopathogenic
- c)Latent
- d)Abortive
Correct answer is option 'B'. Can you explain this answer?
Which of the following infection is also called as lytic infection?
a)
Null
b)
Cytopathogenic
c)
Latent
d)
Abortive
|
|
Orion Classes answered |
Cytopathogenic infections are also called lytic infections as the cell dies due to lysis. But lytic is not the accurate term, as in some infection cells die without being lysed, that is, by apoptosis or programmed cell death.
Which of the following is not the type of viral infection?- a)Null
- b)Meningitis
- c)Latent
- d)Persistent
Correct answer is option 'B'. Can you explain this answer?
Which of the following is not the type of viral infection?
a)
Null
b)
Meningitis
c)
Latent
d)
Persistent
|
|
Orion Classes answered |
Meningitis is a type of bacterial infection. The interactions between viral and cells can be classified into acutely cytopathogenic, persistent, null, latent, abortive, transforming infections.
Retroviruses are unique among viruses because they:- a)Lack an envelope
- b)Contain RNA as their genetic material
- c)Replicate their RNA genome using reverse transcriptase
- d)Only infect plants
Correct answer is option 'C'. Can you explain this answer?
Retroviruses are unique among viruses because they:
a)
Lack an envelope
b)
Contain RNA as their genetic material
c)
Replicate their RNA genome using reverse transcriptase
d)
Only infect plants
|
|
Orion Classes answered |
Retroviruses are RNA viruses that replicate their RNA genome using an enzyme called reverse transcriptase. Reverse transcriptase converts the viral RNA into DNA, which can then integrate into the host cell's genome. This unique characteristic sets retroviruses apart from other types of viruses.
The lytic cycle of viral reproduction involves:- a)Integration of the viral genome into the host cell's genome
- b)Production of viral progeny and lysis of the host cell
- c)Formation of a dormant viral state within the host cell
- d)Fusion of the viral envelope with the host cell membrane
Correct answer is option 'B'. Can you explain this answer?
The lytic cycle of viral reproduction involves:
a)
Integration of the viral genome into the host cell's genome
b)
Production of viral progeny and lysis of the host cell
c)
Formation of a dormant viral state within the host cell
d)
Fusion of the viral envelope with the host cell membrane
|
|
Orion Classes answered |
In the lytic cycle, the virus enters the host cell, replicates its genetic material, synthesizes viral proteins, assembles new viral particles, and finally lyses (bursts) the host cell, releasing the newly formed viral progeny.
The release of enveloped viruses from the host cell occurs through:- a)Lysis of the host cell
- b)Budding from the host cell membrane
- c)Formation of viral inclusion bodies
- d)Conjugation with other infected cells
Correct answer is option 'B'. Can you explain this answer?
The release of enveloped viruses from the host cell occurs through:
a)
Lysis of the host cell
b)
Budding from the host cell membrane
c)
Formation of viral inclusion bodies
d)
Conjugation with other infected cells
|
|
Orion Classes answered |
Enveloped viruses exit the host cell through a process called budding. During budding, the virus acquires an envelope derived from the host cell's membrane, and it buds off from the cell surface, taking a portion of the membrane with it. This process allows the virus to exit the cell without immediately lysing it.
Which of the following virus promotes cell death by apoptosis?- a)Vaccinia virus
- b)Myxoma virus
- c)HSV
- d)Rubella virus
Correct answer is option 'D'. Can you explain this answer?
Which of the following virus promotes cell death by apoptosis?
a)
Vaccinia virus
b)
Myxoma virus
c)
HSV
d)
Rubella virus
|
|
Orion Classes answered |
Rubella virus, which belongs to the family Togaviridae, expresses proteins that promote the cell death by apoptosis. Vaccinia virus, myxoma virus, herpes simplex virus, etc. are the viruses that inhibit the cell death by apoptosis.
Apoptosis regulates cell numbers.- a)True
- b)False
Correct answer is option 'A'. Can you explain this answer?
Apoptosis regulates cell numbers.
a)
True
b)
False
|
|
Orion Classes answered |
Apoptosis is the process that regulates cell numbers during development. The unique feature of apoptosis is that the dying cell remains intact and its contents stay within the plasma membrane.
The reproductive cycle of a virus typically involves:- a)Binary fission
- b)Meiosis
- c)Mitosis
- d)Hijacking host cellular machinery
Correct answer is option 'D'. Can you explain this answer?
The reproductive cycle of a virus typically involves:
a)
Binary fission
b)
Meiosis
c)
Mitosis
d)
Hijacking host cellular machinery
|
|
Orion Classes answered |
Viruses lack the necessary cellular machinery to replicate on their own. Instead, they hijack the host cell's machinery to reproduce. They utilize the host cell's enzymes, ribosomes, and metabolic pathways to synthesize viral proteins and replicate their genetic material.
Chapter doubts & questions for Viruses and Viral Life Cycle (BIO) - MCAT Biological and Biochemical Foundations 2025 is part of MCAT exam preparation. The chapters have been prepared according to the MCAT exam syllabus. The Chapter doubts & questions, notes, tests & MCQs are made for MCAT 2025 Exam. Find important definitions, questions, notes, meanings, examples, exercises, MCQs and online tests here.
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