intro
MCQs 1:
What facilitates the specific binding of HIV to the CD4 surface molecules on the host membrane?
Topic: HIV Binding Mechanism
Correct Answer: A) gp 120
- The binding of HIV to the host's CD4 surface molecules is a specific process and is facilitated by certain proteins.
- Among the options provided, it's gp 120 that plays a key role in this binding process.
- Thus, the correct answer is A, "gp 120".
MCQs 2:
Into how many distinct stages can the life cycle of HIV be divided?
Topic: Stages of HIV Life Cycle
Correct Answer: D) 6 stages
- HIV, the human immunodeficiency virus, goes through a specific sequence of stages during its life cycle.
- This sequence includes distinct processes such as binding and fusion, reverse transcription, integration, transcription and translation, assembly, and finally, budding and maturation.
- Given this, the correct answer is D — there are 6 stages in the HIV life cycle.
MCQs 3:
The therapeutic approach known as HAART is primarily used to treat which disease?
Topic: Therapeutic Approaches in Disease Management
Correct Answer: C) AIDS
- HAART, standing for Highly Active Anti-Retroviral Therapy, is a combination of medications used in the management of a specific disease.
- This approach combines three or more anti-HIV medications in a single regimen, sometimes referred to as a cocktail.
- The primary disease treated by HAART is HIV, which leads to AIDS.
- Therefore, the correct answer is C — AIDS.
MCQs 4:
People suffering from which disease are most likely to be susceptible to numerous opportunistic diseases?
Topic: Disease Susceptibility
Correct Answer: D) AIDS
- An individual's susceptibility to opportunistic diseases often increases when their immune system is significantly compromised.
- Among the diseases listed, AIDS, or Acquired Immunodeficiency Syndrome, is widely known to heavily compromise the immune system.
- This leaves individuals with AIDS particularly vulnerable to a broad range of opportunistic diseases.
- Thus, the correct answer is D — AIDS.
MCQs 5:
Which component is responsible for binding the virus to cells that have sialic acid on their membranes?
Topic: Viral Attachment Mechanisms
Correct Answer: A) Hemagglutinin (HA)
- The process of viral attachment to host cells is facilitated by specific components present on the surface of the virus.
- In this context, Hemagglutinin (HA) plays a crucial role in binding the virus to cells that feature sialic acid on their membranes.
- Therefore, the correct answer is A — Hemagglutinin (HA).
MCQs 6:
What is the term for viruses that target the immune system, use RNA as their genetic material, reproduce slowly, and have a long incubation period?
Topic: Viral Classification
Correct Answer: B) Lentiviruses
- Viruses can be classified based on several characteristics, including their target cells, genetic material, replication speed, and incubation period.
- Lentiviruses, a subgroup of retroviruses, are characterized by their RNA genetic material, slow replication process, and long incubation periods.
- Hence, the correct answer is B — Lentiviruses.
MCQs 7:
Which aspect is the genome of the influenza virus associated with?
Topic: Influenza Virus Structure
Correct Answer: B) 5 viral proteins
- The structure of a virus, including its genome, is associated with specific components that facilitate its ability to infect and replicate within host cells.
- In the case of the influenza virus, its genome is associated with 5 types of proteins.
- Therefore, the correct answer is B — 5 viral proteins.
Question 8:
What is the shape of the Poliovirus?
Topic: Viral Structure
Correct Answer: D) Golf ball shape
- The structure of viruses can vary significantly, with shapes ranging from helical to complex.
- Poliovirus, a member of the Enterovirus genus, is known for its specific form.
- It is characterized by a spherical shape, similar to a golf ball.
- Thus, the correct answer is D — Golf ball shape.
Question 9:
What is the calculated replication time of some viruses, and within what time frame can they destroy a host cell?
Topic: Viral Replication
Correct Answer: B) 70 seconds, 10 minutes
- The replication time of viruses can vary widely, and the speed of this process contributes significantly to their ability to cause disease.
- It's been calculated that some viruses can replicate themselves within just 70 seconds.
- Furthermore, in as little as 10 minutes, these viruses can destroy a host cell after making hundreds of copies of themselves.
- Therefore, the correct answer is B — 70 seconds, 10 minutes.
Question 10:
What type of RNA does the influenza virus possess?
Topic: Viral Genetic Material
Correct Answer: C) Single-stranded segmented RNA
- The genetic material of viruses can be either RNA or DNA, and it can be single- or double-stranded.
- Influenza viruses are a type of RNA virus.
- Specifically, they carry single-stranded RNA that is segmented into separate RNA pieces.
- Hence, the correct answer is C — Single-stranded segmented RNA.
Question 11:
What type of genetic material and protein coat does HIV possess?
Topic: HIV Structure
Correct Answer: B) Single-stranded RNA (ssRNA)
- HIV, the Human Immunodeficiency Virus, is known for its unique structure, which aids its ability to invade host cells.
- It possesses a protein coat and genetic material.
- Specifically, its genetic material is single-stranded RNA (ssRNA).
- Therefore, the correct answer is B — Single-stranded RNA (ssRNA).
Question 12:
Which of the following is not a criterion used to classify viruses?
Topic: Viral Classification
Correct Answer: A) Type of reproduction
- Viruses are classified based on several factors, including their nucleic acid type, presence or absence of an envelope, and size and shape.
- However, the type of reproduction is not among the standard criteria used for viral classification.
- Thus, the correct answer is A — Type of reproduction.
Question 13:
What is the term for an RNA virus that has a DNA stage in its life cycle?
Topic: Viral Life Cycles
Correct Answer: D) Retrovirus
- Viruses follow diverse life cycles, with some RNA viruses undergoing a DNA stage.
- These viruses are specifically known as retroviruses.
- Therefore, the correct answer is D — Retrovirus.
Question 14:
What are the two major protein components that make up the spikes in HIV?
Topic: HIV Structure
Correct Answer: A) gp-120 and gp-41
- HIV, the Human Immunodeficiency Virus, has a unique structure that includes spikes made up of protein components.
- These include two major proteins: gp-120 and gp-41.
- The spike's head comprises gp120, and its tail is made of gp41.
- Therefore, the correct answer is A — gp-120 and gp-41.
Question 15:
What do the proteins on a virus's surface use to recognize its target on the host cell's surface?
Topic: Viral Recognition Mechanism
Correct Answer: A) Proteins or sugars
- Viruses use specific methods to recognize and attach to host cells.
- Proteins on the virus's surface play a crucial role in recognizing targets on a host cell's surface.
- These targets are usually proteins or sugars.
- Hence, the correct answer is A — Proteins or sugars.
Question 16:
What is accurate about the envelope of a virus?
Topic: Viral Envelope Characteristics
Correct Answer: D) All of the above
- The envelope of a virus carries several defining attributes, contributing to its ability to infect host cells.
- It is typically derived from the host cell membrane and is lipoprotein in nature.
- Moreover, it features projecting spikes on the surface.
- Therefore, the correct answer is D — All of the above.
Question 17:
What is the comparative diameter ratio between E.coli and HIV?
Topic: Comparative Sizes of Microorganisms
Correct Answer: B) One twentieth
- Comparing the diameters of various pathogens provides insight into their relative sizes.
- The diameter of the HIV particle is significantly smaller than that of E.coli.
- It is approximately one twentieth of the length of an E.coli bacterium, highlighting its microscopic size.
- Therefore, the correct answer is B — One twentieth.
Question 18:
Which geometric shape commonly describes the capsid shape of viruses?
Topic: Viral Capsid Shapes
Correct Answer: C) Icosahedron
- Viral capsids come in various geometric shapes, which contribute to their unique structural characteristics.
- One of the most common shapes for a viral capsid is an icosahedron.
- This structure provides stability and efficiency for the virus.
- Therefore, the correct answer is C — Icosahedron.
Question 19:
Which enzyme is not encoded by the pol gene in viruses?
Topic: Viral Genes and Enzymes
Correct Answer: D) RNA polymerase
- The pol gene in viruses encodes several crucial enzymes that facilitate the viral replication process.
- However, not all enzymes involved in virus replication are encoded by the pol gene.
- Specifically, the pol gene does not encode for RNA polymerase.
- Hence, the correct answer is D — RNA polymerase.
Question 20:
In a bacteriophage, which structure is more intricate than the others?
Topic: Bacteriophage Structure Complexity
Correct Answer: C) Head
- Bacteriophages, viruses that infect bacteria, have distinct structural components.
- Each of these parts - the body, tail, and head - has a unique structure and complexity.
- While each part is essential, the head of a bacteriophage is often more intricate than the other parts.
- Hence, the correct answer is C — Head.
Question 21:
What is the term for the outer protein covering present in viruses?
Topic: Viral Covering
Correct Answer: A) Capsid
- Viruses are composed of several layers that serve various functions.
- The outermost layer, often made of protein, plays a significant role in protecting the virus and facilitating its attachment to host cells.
- This outer protein layer is referred to as the capsid.
- Thus, the correct answer is A — Capsid.
Question 22:
What type of viruses are bacteriophages?
Topic: Bacteriophage Classification
Correct Answer: A) Double-stranded DNA
- Bacteriophages are a category of viruses that have a specific target: bacteria.
- They are categorized based on their type of genetic material.
- Bacteriophages are typically double-stranded DNA viruses.
- Therefore, the correct answer is A — Double-stranded DNA.
Question 23:
Which of the following viruses is characterized by a spherical shape?
Topic: Virus Morphology
Correct Answer: B) Polio
- Viruses come in a variety of shapes, each unique to its type.
- While many viruses are complex in shape, some, like the Polio virus, are spherical.
- This sphere-like morphology is distinct to the Polio virus among the options provided.
- Therefore, the correct answer is B — Polio.
Question 24:
The configuration of neuraminidase or sialidase can be best described as which of the following?
Topic: Enzyme Structures
Correct Answer: A) Mushroom shape
- Enzymes in viruses exhibit various forms, impacting their function and interaction with host cells.
- Neuraminidase or sialidase, an enzyme in certain viruses, has a unique mushroom shape.
- This shape allows it to interact effectively with other molecules.
- Thus, the correct answer is A — Mushroom shape.
Question 25:
Which treatment approach is considered most effective for HIV infection?
Topic: HIV Treatment
Correct Answer: D) Highly active antiretroviral therapy
- Several strategies are employed in the treatment of HIV, aiming to control virus replication and halt disease progression.
- Highly active antiretroviral therapy (HAART) combines three or more anti-HIV medications in a daily regimen, sometimes referred to as a "cocktail".
- HAART has proved to be the most effective treatment strategy for HIV.
- Hence, the correct answer is D — Highly active antiretroviral therapy.
Question 26:
Why are phage viruses typically abundant in the intestines of humans and animals?
Topic: Phage Viruses Habitat
Correct Answer: A) Abundant bacteria are present
- Phage viruses have a specific habitat preference based on their target host and environmental conditions.
- In the case of human and animal intestines, the environment is rich with their primary targets, bacteria.
- While water and nutrients are also abundant in the intestines, it is the high concentration of bacteria that primarily attracts phage viruses.
- Therefore, the correct answer is A — Abundant bacteria are present.