BIOL212 W6-1

<p>Amoeba (C)</p> Signup and view all the answers

<p>Marine amoebae (A)</p> Signup and view all the answers

<p>Single-stranded circular DNA (D)</p> Signup and view all the answers

<p>Post-weaning Multisystemic Wasting Syndrome (PMWS) (A)</p> Signup and view all the answers

<p>Class VII (dsDNA) (D)</p> Signup and view all the answers

<p>Enzymatic proteins (A)</p> Signup and view all the answers

<p>Class IV viruses are devoid of prokaryotic hosts. (C)</p> Signup and view all the answers

<p>Transition from RNA to DNA (A)</p> Signup and view all the answers

<p>Class I (dsDNA) (B)</p> Signup and view all the answers

<p>Double-stranded DNA (A)</p> Signup and view all the answers

<p>Class VI (A)</p> Signup and view all the answers

<p>Class IV (B)</p> Signup and view all the answers

<p>They need a double-stranded DNA intermediate (D)</p> Signup and view all the answers

<p>RNA replicase synthesizes mRNA from their RNA genome (B)</p> Signup and view all the answers

<p>They have double-stranded RNA (C)</p> Signup and view all the answers

<p>To convert RNA to DNA (B)</p> Signup and view all the answers

<p>Class IV (A)</p> Signup and view all the answers

<p>Class IV (A)</p> Signup and view all the answers

<p>They use a negative-strand RNA template for mRNA synthesis (D)</p> Signup and view all the answers

<p>It can exit the cell without lysing the host. (D)</p> Signup and view all the answers

<p>The encoding of T7 RNA polymerase for efficient replication. (D)</p> Signup and view all the answers

<p>Rolling circle replication. (A)</p> Signup and view all the answers

<p>Made of 60 asymmetric protein units organized in a cubical structure. (D)</p> Signup and view all the answers

<p>It leads to cell lysis and the release of new virions. (C)</p> Signup and view all the answers

<p>Develops without host cell contact (C)</p> Signup and view all the answers

<p>SSV has spindle-shaped virions while SIFV has helical rods (D)</p> Signup and view all the answers

<p>Cytoplasm (B)</p> Signup and view all the answers

<p>It leads to extensive skin scarring (C)</p> Signup and view all the answers

<p>It is a model for studying smallpox (B)</p> Signup and view all the answers

<p>RNA archaeal viruses (B)</p> Signup and view all the answers

<p>~190 kbp (C)</p> Signup and view all the answers

<p>It helps in the integration of the phage into the host genome. (A)</p> Signup and view all the answers

<p>It alternates between lytic and lysogenic cycles. (B)</p> Signup and view all the answers

<p>It is linear and encodes proteins for both cycles. (D)</p> Signup and view all the answers

<p>The type of tail fibers it possesses. (C)</p> Signup and view all the answers

<p>The host cell lyses and releases mature virions. (D)</p> Signup and view all the answers

<p>It generates mutations that can be used for genetic studies. (A)</p> Signup and view all the answers

<p>It involves repeated transposition to different sites in the host genome. (A)</p> Signup and view all the answers

<p>They are primarily enveloped and single-stranded DNA viruses. (C)</p> Signup and view all the answers

<p>Loss of contact inhibition leading to malignancy (A)</p> Signup and view all the answers

<p>It inhibits the function of tumor suppressor proteins pRb and p53. (A)</p> Signup and view all the answers

<p>They can establish latency and reactivate under certain conditions. (A)</p> Signup and view all the answers

<p>Host cytoplasmic membrane fuses with the viral envelope. (A)</p> Signup and view all the answers

<p>Immediate early mRNA; it encodes regulatory proteins for viral gene expression. (C)</p> Signup and view all the answers

<p>30% (C)</p> Signup and view all the answers

<p>By attaching to the pilus (B)</p> Signup and view all the answers

<p>It directly functions as mRNA. (A)</p> Signup and view all the answers

<p>Symptoms may only develop when the immune system is weakened. (B)</p> Signup and view all the answers

<p>It converts positive RNA into negative RNA. (B)</p> Signup and view all the answers

<p>Alzheimer's disease (A)</p> Signup and view all the answers

<p>After lysis of the host cell. (D)</p> Signup and view all the answers

<p>Infectious mononucleosis (B)</p> Signup and view all the answers

<p>Malaria co-infection (A)</p> Signup and view all the answers

<p>Serological mismatch between donor and recipient (C)</p> Signup and view all the answers

<p>B-lymphocytes (C)</p> Signup and view all the answers

<p>It is complex and may involve multiple viral genes. (A)</p> Signup and view all the answers

<p>235 kb (B)</p> Signup and view all the answers

<p>Epstein-Barr virus (C)</p> Signup and view all the answers

<p>Weakening of the immune system (C)</p> Signup and view all the answers

<p>It must first be transcribed by viral replicase. (D)</p> Signup and view all the answers

<p>It enables antigenic shift through reassortment. (B)</p> Signup and view all the answers

<p>Human rabies immune globulin (C)</p> Signup and view all the answers

<p>Immediate postexposure prophylaxis (PEP). (B)</p> Signup and view all the answers

<p>It has an enveloped and non-uniform morphology. (C)</p> Signup and view all the answers

<p>It assists in the breakdown of host cell membrane components. (D)</p> Signup and view all the answers

<p>Through regular vaccination of pets. (C)</p> Signup and view all the answers

<p>Converts the viral genome into mRNA. (C)</p> Signup and view all the answers

<p>Effective budding from the host cell. (C)</p> Signup and view all the answers

<p>Absence of immunity to new forms (D)</p> Signup and view all the answers

<p>H5N1 (B), H7N9 (C)</p> Signup and view all the answers

<p>Double-Stranded RNA Viruses (D)</p> Signup and view all the answers

<p>Spanish Flu (A)</p> Signup and view all the answers

<p>Multiple distinct RNA segments (A)</p> Signup and view all the answers

<p>They can cause sudden outbreaks due to population immunity gaps. (C)</p> Signup and view all the answers

<p>Rotavirus (D)</p> Signup and view all the answers

<p>H5N1 (C)</p> Signup and view all the answers

<p>Gastroenteritis (C)</p> Signup and view all the answers

<p>Increases likelihood of zoonotic spillover (B)</p> Signup and view all the answers

<p>It acts as a primer for DNA synthesis. (D)</p> Signup and view all the answers

<p>Viral tRNA, reverse transcriptase, and the RNA genome. (A)</p> Signup and view all the answers

<p>Hepadnaviruses employ a protein primer for DNA synthesis. (C)</p> Signup and view all the answers

<p>PrPSc has a different conformation. (A)</p> Signup and view all the answers

<p>By converting PrPC into PrPSc. (B)</p> Signup and view all the answers

<p>They assist in the integration of viral DNA into the host genome. (C)</p> Signup and view all the answers

<p>It can remain latent or be expressed to produce new virions. (D)</p> Signup and view all the answers

<p>It leads to the destruction of brain tissue. (A)</p> Signup and view all the answers

<p>Chronic wasting disease (C)</p> Signup and view all the answers

<p>It features a double-stranded DNA genome with overlapping genes. (A)</p> Signup and view all the answers

<p>By the amino acid sequence of the prion protein. (C)</p> Signup and view all the answers

<p>Development of Hepatocellular carcinoma (HCC) (A)</p> Signup and view all the answers

<p>Double-stranded covalently closed circular DNA (cccDNA) (A)</p> Signup and view all the answers

<p>Presence of incomplete vaccination coverage (B)</p> Signup and view all the answers

<p>Synthesis of genomic DNA from RNA template (A)</p> Signup and view all the answers

<p>Approximately 250 million individuals globally (B)</p> Signup and view all the answers

<p>Transformation of viral DNAs into cccDNA (B)</p> Signup and view all the answers

<p>Technology for recombinant HBsAg production (C)</p> Signup and view all the answers

<p>Inclusion of chronic carriers and incomplete vaccination coverage (A)</p> Signup and view all the answers

<p>Development of liver cirrhosis (C)</p> Signup and view all the answers

<p>Residents in China (C)</p> Signup and view all the answers

Viral genomes differ significantly in size, ranging from a few thousand to over a million base pairs.

The smallest known viral genome, the circovirus, is a single-stranded DNA with about 1.75 kilobases.

The largest known viral genome, the Pandoravirus, is a double-stranded DNA genome.

Viral genomes can be made of DNA or RNA, with RNA genomes generally smaller than DNA genomes.

Pandoravirus infects certain types of marine amoebae and is larger than some bacteria.

Circoviruses can cause post-weaning multisystemic wasting syndrome (PMWS) and porcine dermatitis in animals.

Amoeba are unicellular organisms that can be hosts to bacteria, such as Legionella, which can cause respiratory diseases in humans.

A classification system for viruses based on their genome structure and mRNA production.

Viruses with double-stranded DNA genomes.

Single-stranded positive or plus-strand DNA viruses; require a double-stranded DNA replicative form as an intermediate.

Single-stranded (+) RNA viruses; their genome is mRNA.

Single-stranded (-) RNA viruses; require RNA replicase to produce a complementary (+) strand for mRNA and more genomic (-) strands.

Double-stranded RNA viruses; their replication process is similar to class V RNA viruses.

Single-stranded (+) RNA viruses that replicate through a DNA intermediate; they use reverse transcriptase to copy RNA into DNA.

An enzyme that copies RNA into DNA.

A type of genetic material composed of two complementary DNA strands.

A type of genetic material composed of a single RNA strand.

Classification system for viruses based on their method of mRNA production.

The process of making viral proteins. It happens in stages called early and late proteins.

Viruses may have evolved after cells or before.

Viral proteins produced soon after infection, usually enzymes that help viral replication

Viral proteins synthesized later, often structural proteins for building new viruses

A filamentous bacteriophage that infects E. coli and can be released without lysing the host cell. Its coat proteins cover the DNA as it exits the cell envelope.

M13 uses rolling circle replication to create new phage DNA. Its coat proteins cover the DNA as it exits the cell envelope, leading to a chronic infection.

A double-stranded DNA bacteriophage that infects E. coli, known for its efficient replication process and its use in biotechnology.

T7 replicates using a specific DNA polymerase, involving terminal repeats and concatemer formation. The phage inhibits the host's restriction system.

T7 encodes its own RNA polymerase, which is widely used in biotechnology due to its high efficiency and specificity.

A spindle-shaped archaeal virus that infects hyperthermophilic Crenarchaeota. It forms rosettes and has a linear DNA genome.

A rigid, helical rod-shaped archaeal virus that infects Sulfolobus. It has a linear DNA genome.

An archaeal virus that infects Acidianus. It's unique because it can develop without host cell contact, forming extended tails, and is lysogenic.

An archaeal virus that infects Pyrococcus. It's released without lysis, likely through budding, and is heat-stable.

Pox viruses replicate entirely within the cytoplasm of the host cell, not in the nucleus.

Adenoviruses replicate on both DNA template strands of the host cell.

A large, double-stranded DNA virus that causes smallpox, a historically significant disease. It was eradicated through vaccination.

Two modes of bacteriophage replication. Lytic cycle involves phage replication and host cell lysis, while lysogenic cycle integrates the phage into the host genome as a prophage.

The process by which a genetic element (like the Mu phage genome) moves from one location in the genome to another.

An enzyme required for the integration of the Mu phage genome into the bacterial chromosome.

The integrated form of a bacteriophage's genome within the bacterial chromosome during the lysogenic cycle.

The range of organisms a particular virus can infect.

Viruses that infect archaea, often with double-stranded circular DNA genomes.

Two major phyla within the domain Archaea, many of which are hosts to archaeal viruses.

SV40 integrates its DNA into the host's genome and expresses a protein called large T antigen, which inhibits tumor suppressor proteins like pRb and p53, leading to uncontrolled cell growth and cancer.

A large group of double-stranded DNA viruses that cause various diseases like fever blisters, venereal herpes, chicken pox, shingles, mononucleosis, and some even cause cancer.

Herpesviruses can remain dormant in the body (latent) for extended periods, reactivating under stress or a weakened immune system.

Herpesviruses replicate through a rolling circle mechanism, where the viral DNA creates multiple copies. This replication occurs within the nucleus of the host cell.

A disease caused by Cytomegalovirus (CMV), occurring in approximately 30% of patients undergoing allogeneic transplantation and 5% of those undergoing autologous transplantation.

A strong and constitutive promoter commonly used in genetic engineering vectors for mammalian cells, known for its ability to drive high levels of gene expression.

The virus responsible for cold sores (fever blisters), affecting the lips and mouth, and also causing genital herpes. Transmitted through direct contact with sores or bodily fluids.

A phenomenon where a single DNA sequence encodes for multiple proteins, seen in some viruses, including Bacteriophage MS2.

A technique involving two constructs to study the location and function of specific proteins within cells, using MS2 bacteriophage.

A protein component of the Bacteriophage MS2 outer shell, interacting with a stem-loop structure from the phage genome for spontaneous assembly.

A herpesvirus that causes infectious mononucleosis ("mono"), a common illness characterized by fatigue, sore throat, and swollen lymph nodes. Most people are infected by their teens, but not everyone develops symptoms.

EBV can remain dormant or inactive within B-lymphocytes (a type of white blood cell), which are part of the immune system. This latency can last for years, potentially leading to reactivation later on.

EBV has been linked to various cancers, including Burkitt's lymphoma, a type of non-Hodgkin lymphoma common in children with malaria. EBV can also be involved in nasopharyngeal carcinoma, a type of cancer affecting the upper part of the throat.

A common herpesvirus that infects most people, often without causing symptoms. It can cause problems, especially in people with weakened immune systems, such as transplant recipients.

CMV infection is a significant concern after organ transplantation. If the recipient is CMV-negative and the donor is CMV-positive, the recipient is at risk of developing CMV disease due to immunosuppression from transplant medications.

A type of non-Hodgkin lymphoma, often found in children, and associated with EBV infection and malaria. EBV is thought to contribute to the development of this cancer in individuals with weakened immune systems.

EBV can induce changes in cells by introducing viral genes or manipulating cellular processes, potentially leading to cancer development. This is a complex process, likely involving multiple viral genes and various cellular pathways.

Currently, there is no vaccine available to prevent infection with Epstein-Barr Virus.

Viruses formed when two different influenza strains infect the same cell, resulting in a new strain with a unique surface protein combination.

They express a unique combination of surface proteins, making them unrecognizable to the immune system's antibodies.

Because the population lacks immunity to these new strains due to their unique surface proteins.

A viral genome broken into multiple pieces, allowing for more genetic variety when viruses recombine.

A type of influenza A virus responsible for the 1918 Spanish flu pandemic.

Viruses that can jump from animals to humans.

A type of viral genetic material composed of two complementary RNA strands.

A type of double-stranded RNA virus that can cause diseases like diarrhea and respiratory infections.

A type of reovirus that causes diarrhea in young children (6-24 months old).

Flu viruses can rapidly evolve, creating new strains with unique surface proteins that are highly contagious and evade the immune system, often causing outbreaks and pandemics.

A virus that carries its genetic information as a single-stranded RNA molecule with negative polarity. This means the RNA strand is complementary to a messenger RNA (mRNA) and needs to be transcribed into a positive strand before protein synthesis can occur.

Rabies virus is a classic example of a negative-strand RNA virus. It belongs to the rhabdovirus family and has a bullet-shaped structure with an enveloped and helical nucleocapsid.

Rabies virus first needs to be transcribed by a viral replicase enzyme found in the host's cytoplasm. This creates two types of RNA: mRNAs to produce viral proteins and a positive strand RNA copy of the complete viral genome.

Antigenic shift is a phenomenon where different strains of a segmented RNA virus, like influenza, infect the same host cell. This can lead to reassortment of the RNA genome segments, creating a novel virus with a combination of genetic material from the original strains.

Hemagglutinin (HA) is a protein on the surface of influenza viruses that helps the virus attach to and enter host cells. It also stimulates the immune system and antibodies against hemagglutinin can prevent infection.

Neuraminidase (NA) is another surface protein on influenza viruses. It helps the virus detach from infected cells and spread to new cells. It also breaks down sialic acid, a component of the host cell membrane.

The influenza virus genome is segmented. This means its genetic information is divided into separate pieces of RNA, unlike most other viruses that have a single piece of genetic material.

Antigenic shift happens when different strains of influenza virus, with segmented genomes, recombine to create a new virus with a completely different combination of genes. Antigenic drift, on the other hand, involves small mutations in the viral genes, like hemagglutinin, leading to gradual changes in the virus's ability to evade the immune system.

Rabies can be prevented by vaccinating pets and staying away from wildlife. If an individual is exposed to the virus, postexposure prophylaxis (PEP) involving human rabies immune globulin (HRIG) and rabies vaccine should be administered immediately. PEP can prevent the development of rabies.

Rabies is a fatal disease caused by bites from infected animals, usually wild animals or pets. The virus travels to the brain, causing inflammation and ultimately leading to death. Once symptoms develop, rabies is almost always fatal.

The genetic material of a retrovirus, consisting of two identical RNA molecules. Unlike most viruses, its RNA is not directly used as mRNA.

The process of incorporating retroviral DNA into the host cell's genome, making it a permanent part of the host's genetic material.

A gene in retroviruses responsible for encoding several small proteins, forming the viral capsid structure, a shell that encapsulates the genetic material.

A gene in retroviruses that produces a large polyprotein, which is later cleaved into various enzymes like reverse transcriptase and integrase, crucial for replication.

A gene in retroviruses that encodes proteins that make up the viral envelope, a protective outer layer that surrounds the virus.

A group of DNA viruses that use reverse transcriptase and have unusual genomes. Examples include Hepatitis B.

A global health issue caused by Hepatitis B Virus (HBV), affecting millions worldwide. It can lead to acute hepatitis, liver cirrhosis, liver failure, and liver cancer.

A covalently closed circular DNA form of the HBV genome that persists in the host cell's nucleus and acts as the template for RNA transcription, causing chronic HBV infection.

A vaccine made using recombinant HBsAg (surface antigen) that provides protection against HBV infection. It has been successful in controlling HBV infections but challenges remain due to chronic infections and incomplete vaccination coverage.

A major change in the influenza virus due to the reassortment of its segmented genome. It occurs when two different influenza subtypes infect the same cell, leading to a new strain with a unique surface protein combination.

Gradual changes in the influenza virus due to small mutations in its genes, such as hemagglutinin. This can lead to changes in the virus's ability to evade the immune system.

A surface protein on influenza viruses that binds to host cells, helping the virus enter and infect them. It also triggers an immune response. Antibodies to HA can prevent infection.

A surface protein on influenza viruses that helps the virus detach from infected cells and spread, facilitating the spread of infection.

A viral genome consisting of multiple separate pieces of RNA, as seen in influenza. This allows for greater genetic variation through reassortment, which can lead to new strains with a unique combination of genes.

A prion is a type of infectious agent that's made entirely of protein, unlike viruses and bacteria that have genetic material (DNA or RNA). Prions are misfolded versions of normal proteins that can cause other normal proteins to misfold, creating a chain reaction.

Prion diseases are fatal neurodegenerative diseases caused by the accumulation of misfolded prion proteins in the brain. These misfolded proteins aggregate and form plaques that damage brain tissue, leading to dementia and death.

PrPC stands for prion protein cellular. It's the normal, non-infectious form of the prion protein found in healthy animals, including humans.

PrPSc stands for prion protein scrapie. It's the abnormal, infectious form of the prion protein that causes disease.

PrPSc can spread by converting normal PrPC into its infectious form. This misfolding process is thought to be the primary way prion diseases spread.