Microbiology Hardest Trivia Test!

A viral capsid is the protein coat that surrounds and protects the genetic material of a virus. It is composed of individual subunits called capsomeres, which come together to form the overall structure of the capsid. Therefore, the statement that a viral capsid is made up of subunits called capsomeres is true.

AIDS is caused by a retrovirus. Retroviruses are RNA viruses that replicate by reverse transcription, which involves the conversion of their RNA genome into DNA. This DNA is then integrated into the host cell's genome, leading to the production of new viral particles. HIV, the virus that causes AIDS, is a type of retrovirus. It infects and destroys certain immune cells, weakening the immune system and making individuals more susceptible to infections and diseases.

Hepadnaviruses are a type of virus that specifically infects the liver. They are known to cause hepatitis B, a viral infection that primarily affects the liver. Hepadnaviruses have a unique ability to replicate their DNA using a reverse transcriptase enzyme, which allows them to integrate their genetic material into the host's DNA. This integration can lead to chronic liver infection and potentially long-term complications such as liver cirrhosis or liver cancer. Therefore, hepadnaviruses are the correct answer to the question.

Hepatovirus is the correct answer because it specifically refers to viruses that infect the liver. Togavirus, enterovirus, and papillomavirus are not known to primarily infect the liver.

Reactivation of chickenpox long after the initial infection leads to the disease called shingles. Shingles is caused by the varicella-zoster virus, which remains dormant in the body after a person recovers from chickenpox. When the virus reactivates, it causes a painful rash that typically appears in a band or strip on one side of the body. Shingles is not directly linked to cancer, but it can occur in individuals with weakened immune systems, such as those undergoing cancer treatment.

Retroviruses are a type of virus that can cause various diseases in humans. Among the options provided, AIDS is the correct answer because it is caused by the human immunodeficiency virus (HIV), which belongs to the retrovirus family. HIV attacks the immune system, specifically targeting CD4+ T cells, leading to a weakened immune system and making individuals more susceptible to infections and certain types of cancer.

Hepadnaviruses do not typically cause colds. Hepadnaviruses are a family of viruses that primarily infect the liver and are responsible for diseases such as hepatitis B. Colds, on the other hand, are usually caused by rhinoviruses or other respiratory viruses. Therefore, the statement that hepadnaviruses typically cause colds is incorrect.

A viral genome may consist of either RNA or DNA because viruses can have either RNA or DNA as their genetic material. Some viruses have RNA genomes, such as the flu virus or HIV, while others have DNA genomes, like the herpes virus. The type of genetic material a virus possesses is determined by its specific characteristics and evolutionary history.

Oncogenes are viral genes that have the ability to promote uncontrolled division of host cells. This means that when these genes are activated or expressed, they can cause cells to divide and replicate in an unregulated manner, leading to the development of tumors and cancer. Therefore, the statement "Oncogenes are viral genes that promote uncontrolled host cell division" is true.

A teratogen is a drug or agent that can cause defects during embryonic development. It can interfere with the normal growth and development of the fetus, leading to structural abnormalities or functional impairments. Teratogens can include substances such as certain medications, chemicals, infections, and environmental factors. They can have varying effects depending on the timing and duration of exposure, as well as individual susceptibility. Understanding teratogens is important in prenatal care to minimize the risk of harm to the developing fetus.

A virus is a microscopic infectious agent that consists of genetic material (DNA or RNA) enclosed in a protein coat called a capsid. The capsid provides protection to the genetic material and helps in the attachment of the virus to host cells. It is an essential component of the virus structure and plays a crucial role in the infection process. The other options, envelope, nucleon, and virion, do not accurately describe the protein coat of a virus.

A viral capsid is the protein coat that surrounds the genetic material of a virus. It is made up of small units called capsomeres. These capsomeres come together to form the structure of the capsid, providing stability and protection to the viral genome. Liposomes are lipid-based vesicles and are not typically found in viral capsids. Nucleons are subatomic particles found in atomic nuclei and are unrelated to viral capsids. Triglycerides are a type of fat molecule and are also not relevant to viral capsids.

DNA viruses are grouped into families based on whether or not they have an envelope, whether their DNA is single or double stranded, and whether their DNA is linear or circular. This means that the classification of DNA viruses is determined by these three factors, and all of them are taken into consideration when grouping them into families.

In a typical virus replication cycle, the first step is adsorption, where the virus attaches itself to the host cell. This is followed by penetration, where the virus enters the host cell and releases its genetic material. The next step is synthesis, where the viral genetic material is replicated and new viral proteins are produced. Finally, maturation occurs, where the newly formed viral particles are assembled and released from the host cell. Therefore, the correct order of steps in a typical virus replication cycle is adsorption, penetration, synthesis, and maturation.

During the synthesis phase of viral replication, bacteriophage DNA is transcribed to mRNA. This is the phase where the viral genetic material is replicated and new viral components, including mRNA, are synthesized. The mRNA produced during this phase will serve as the template for protein synthesis, allowing the virus to produce the proteins necessary for its replication and assembly.

During viral maturation, new viral components are assembled to form complete virions. This process involves the packaging of viral genetic material into a protein coat, as well as the incorporation of other viral proteins and enzymes. This assembly step is crucial for the formation of infectious viral particles that can go on to infect new host cells. Viral maturation occurs after viral absorption, which is the initial step in the viral life cycle where the virus attaches to and enters the host cell.

A complete virus particle is called a virion. A virion consists of a nucleic acid genome (either DNA or RNA) enclosed in a protein coat called a capsid. The capsid protects the viral genome and helps in its transmission from one host to another. The term "virion" is commonly used to describe the infectious form of a virus that can enter and infect a host cell. Prions are infectious proteins that do not have a nucleic acid genome, while viroids are small infectious RNA molecules that do not have a protein coat.

The families of RNA viruses are distinguished from one another by their nucleic acid content, capsid shape, and presence of an envelope. These three characteristics are used to classify and differentiate RNA viruses into different families. Nucleic acid content refers to the type and structure of the RNA present in the virus. Capsid shape refers to the shape and structure of the protein coat surrounding the RNA. The presence or absence of an envelope, which is a lipid membrane surrounding the capsid, is another distinguishing feature. Therefore, all of the above options are correct in distinguishing RNA virus families.

Prions are infectious agents composed solely of proteins. They do not contain any genetic material such as RNA or DNA. These misfolded proteins can induce normal proteins to adopt the abnormal shape, leading to the development of various neurodegenerative diseases called prion diseases. Therefore, the correct answer is "proteins only" as prions are solely composed of proteins.

"Naked" viruses do not have an envelope. Envelope refers to a protective outer layer that surrounds some viruses, which is derived from the host cell's membrane. This envelope helps the virus evade the host's immune system and facilitates its entry into new host cells. However, naked viruses lack this envelope and therefore have a higher susceptibility to environmental factors such as temperature, pH, and chemicals.

The correct answer is bacteria because T-even phages are known to infect bacteria, not human liver cells. Studying these phages has provided valuable insights and information about the mechanisms and behavior of viruses. By studying their life cycles, replication processes, and interactions with bacterial hosts, scientists have gained a better understanding of how viruses function in general.

Most bacteria viruses, also known as bacteriophages, are indeed complex viruses. Bacteriophages are viruses that infect bacteria and have a complex structure, consisting of a protein coat (capsid) that encloses their genetic material (DNA or RNA). They often have additional structures such as tail fibers or tail spikes that allow them to attach to specific receptors on the bacterial cell surface. This complexity enables bacteriophages to effectively infect and replicate within bacterial cells. Therefore, the statement "Most bacteria viruses are complex viruses" is true.

Plaques are areas where bacterial cells have been lysed. This means that the bacterial cells in those areas have ruptured or burst open, releasing their contents. This can occur due to various factors such as viral infection or the action of certain enzymes. The lysis of bacterial cells leads to the formation of clear zones or areas called plaques, which can be observed and measured in laboratory settings.

The growth of a bacteria that contains a prophage represents the lysogenic cycle. In this cycle, the prophage, which is a viral genome, integrates into the bacterial genome and becomes dormant. The host bacteria continues to replicate and pass on the prophage to its daughter cells during cell division. The prophage remains dormant until it is triggered by certain environmental factors, causing it to excise from the bacterial genome and enter the lytic cycle, where it starts replicating and eventually lyses the host cell.

A viral capsid is the protein coat that surrounds the genetic material of a virus. It provides protection to the genetic material and helps in the attachment of the virus to host cells. Lipids, carbohydrates, and nucleic acids are not typically found in the viral capsid. Proteins are the main component of the viral capsid, making them the correct answer.

Chickenpox is caused by the herpes virus. The herpes virus is highly contagious and can be spread through direct contact with an infected individual or through respiratory droplets. It causes an itchy rash and flu-like symptoms. Chickenpox is most common in children but can also affect adults who have not been previously infected. The virus remains dormant in the body after the initial infection and can reactivate later in life, causing a different condition known as shingles.

Rabies is a viral disease that is caused by the Rhabdovirus. It is transmitted through the bite of an infected animal, such as dogs, bats, or raccoons. The virus attacks the central nervous system, leading to inflammation of the brain. Symptoms of rabies include fever, headache, muscle weakness, and eventually, paralysis and death if left untreated. Vaccination is the most effective way to prevent rabies in both animals and humans.

Viruses are infectious agents that are composed of genetic material, either DNA or RNA, surrounded by a protein coat called a capsid. Nucleic acids, which refer to DNA or RNA, are the genetic material that viruses use to replicate and infect host cells. Therefore, nucleic acids are a crucial component of viruses and are found in all types of viruses. The other components listed, such as cell wall, nucleus, and ribosomes, are not typically found in viruses.

A reasonable number of new phages to expect from one round of viral replication in one cell would be 100. This is because during viral replication, the virus hijacks the host cell's machinery to produce multiple copies of itself. These copies, known as progeny or new phages, are released from the infected cell to infect other cells. The number of new phages produced can vary depending on factors such as the type of virus and the efficiency of the replication process. In this case, it is reasonable to expect 100 new phages as a result of one round of viral replication in one cell.

Diseases such as Jacob's disease, kuru, and mad cow disease are caused by prions. Prions are abnormal proteins that can cause normal proteins in the brain to become misfolded and form aggregates. These aggregates can lead to neurodegenerative diseases. Unlike viruses, prions do not have genetic material like RNA or DNA. Instead, they are composed of misfolded proteins that can transmit their abnormal shape to other normal proteins, causing a chain reaction and disease progression.

Retroviruses are unique because they contain the enzyme reverse transcriptase. This enzyme allows retroviruses to convert their RNA genome into DNA, which can then be integrated into the host cell's genome. This process is called reverse transcription and is essential for the replication and survival of retroviruses. Reverse transcriptase is not found in other types of viruses or in normal cellular processes, making it a distinguishing feature of retroviruses.

Rhinovirus is the correct answer because it is a common cause of the common cold. Rhinoviruses are a type of virus that infect the nose and throat, leading to symptoms such as a runny or stuffy nose, sneezing, sore throat, and cough. They are highly contagious and can be easily transmitted through respiratory droplets from an infected person. Rhinoviruses are responsible for a majority of cold cases, making them the most likely culprit when someone develops cold symptoms.

Prophages are a type of virus that can integrate their genetic material into the DNA of their host bacterium. In the case of Clostridium botulinum, the bacterium responsible for botulism, prophages play a role in the production of the toxins that cause the illness. These prophages carry the genes encoding for the production of botulinum toxin, which is one of the most potent neurotoxins known. When the bacterium is infected by the prophage, it activates the genes and produces the toxin, leading to the symptoms of botulism.

Retroviruses have a unique enzyme called reverse transcriptase. This enzyme is responsible for converting the viral RNA of the retrovirus into DNA. This process is known as reverse transcription. The resulting DNA can then be integrated into the host cell's genome and used to produce new viral particles. Therefore, the correct answer is "transcriptase."

Polio is caused by picornavirus. Picornaviruses are a group of small RNA viruses that include the poliovirus. These viruses are known to infect the gastrointestinal tract and can spread to the nervous system, leading to paralysis and other symptoms associated with polio. The poliovirus is a member of the picornavirus family and is the primary cause of polio infections in humans. Other viruses listed, such as flavivirus, retrovirus, and reovirus, are not associated with causing polio.

RNA viruses can contain single stranded RNA or double stranded RNA, but they do not contain both RNA and DNA. Therefore, the correct answer is "RNA and DNA."

Viruses that infect bacteria generally have an elaborate coat or capsid structure, and are known as complex viruses. This is because bacteria are larger and more complex organisms compared to other types of cells that viruses can infect. The elaborate coat or capsid structure of these viruses allows them to effectively invade and infect bacteria, utilizing various mechanisms to hijack the bacterial cell's machinery for their own replication and survival.

Viruses are not able to infect any type of cell. They are highly specific and can only infect certain types of cells that have the necessary receptors for the virus to attach to. This specificity is determined by the viral surface proteins and the specific receptors present on the host cell. Therefore, the statement that a virus is generally able to infect any type of cell is false.

Lysogenic conversion is a phenomenon where a virus transitions from a dormant (temperate) phase to an active (lytic) phase. This process allows the virus to integrate its genetic material into the host bacterium's genome. As a result, the bacterium becomes immune to subsequent infections by the same virus. Therefore, lysogenic conversion prevents bacteria from being infected multiple times by the same virus.

During the maturation phase of viral replication, newly synthesized viral particles are assembled into complete virions. This is the final step in the viral replication cycle, where the individual components of the virus come together to form infectious particles. The maturation phase involves the packaging of viral genetic material into the viral capsid, as well as the acquisition of any necessary viral envelope. Once the virions are fully assembled, they are released from the host cell to infect new cells and continue the viral replication process.

Viral capsids are the protein coats that surround the genetic material of a virus. These capsids are made up of individual units called capsomers. Capsomers are protein subunits that come together to form the overall structure of the viral capsid. They can be arranged in various patterns, such as helical or icosahedral, depending on the type of virus. The capsomers provide stability and protection to the viral genetic material, allowing the virus to infect host cells and replicate.

The correct answer is "latency." Latency refers to the ability of the herpes virus to remain in host cells for an extended period of time without causing any symptoms or being actively replicated. During latency, the virus remains dormant and can reactivate later, leading to recurrent outbreaks or transmission to others. This ability to establish latency is a key characteristic of herpes viruses and contributes to their long-term persistence in the host.

Shedding of new viruses does not necessarily result in lysis and death of the host cell. Some viruses can be released from the host cell without causing cell death, a process known as budding. In this case, the virus is released by taking a portion of the host cell's membrane as it exits, allowing the cell to survive. Therefore, the statement is false.

Chickenpox and shingles are caused by the herpes virus. The herpes virus is a highly contagious virus that can be transmitted through direct contact with an infected person. Chickenpox is the initial infection caused by the herpes virus, which typically occurs in childhood. After the initial infection, the virus remains dormant in the body and can reactivate later in life, causing shingles. Shingles is characterized by a painful rash that usually appears on one side of the body. Both chickenpox and shingles are caused by the same herpes virus.