Bio 2 Monday Tests_Mrs.Flock's Class

When & how can a virus reproduce?

When a virus attaches to a host cell they use the raw materials and enzymes of the host cell, they also use the lactic cycle.

Smallpox is an example of a

viral disease.

What viral parts are made inside a cell? where do the raw materials come from?

viral proteins and nucleic acids; from the viral DNA or RNA injected into the cell

What happens when prions get into the brain?

They form insoluble deposits in the brain

What are the Three Priorities?

Safety of the human population, Euthanasia of the animals with minimal suffering, gathering of scientific samples

Do viruses have ribosomes like cells?

They lack ribosomes

What is a bacteriophage?

A virus that attacks bacteria

What is an attenuated virus?

A weakened, less vigorous virus.

How many sides does the head or capsid of a bacteriophage have?

20 triangular sides

T-bacteriophages have what nucleic acid at their core?

DNA

Give 2 examples of latent viruses.

HIV And Herpes

What proteins do our cells make to help protect us from viruses?

Protease

What came of this conversation?

They determined that they wouldn't tell anyone and would just wait to see if they got sick because they didn't want to be sent to solitary.

Outside of a host cell

viruses are inactive.

Family names for viruses end in

-viridae

Genus names for viruses end in

-virus.

How many monkeys out of the original shipment did Bill Volt count as dead within one month's time?

29

Who is Peter Jahrling?

A civilian virologist at the Institute, he performed research on hot viruses, except for Ebola and Marburg

What is meant by a viral species?

A group of viruses sharing the same genetic information and ecological niche (host)

How long does a herpes infection last?

A life time.

What is a prophage?

A prophage happens when viral DNA joins host DNA forming it

What covers the outside of a virus and what is it called?

A protective envelope, called a capsid

What causes the phage or viral DNA to start replicating?

An activation signal occurs

List the 5 steps of the Lytic cycle in viruses.

Attachment to the call, Penetration of viral DNA or RNA, Replication (Biosynthesis) of new viral proteins and nucleic acids, Assembly (Maturation) of the new viruses, Release of the new viruses into the environment (cell lyses)

Place these steps of the lytic cycle in order: maturation, penetration, release, biosynthesis, and attachment.

Attachment, penetration, biosynthesis, maturation, release.

What does BSE stand for and what is the common name for this prion disease?

BSE: Bovine Spongiform Encephalitis Mad Cow Disease

Explain how viruses were first discovered.

Beijerinck discovered it in 1897, after he filtered infected plant juices and sprayed it on healthy plants and it made them sick.

What is meant by cell lyses?

Break open,the cell does this when it's finished.

How is the subspecies for a virus designated?

By a number

Give an example of a virus that remains dormant in the nervous system tissues for many years.

Chickenpox

______names are used for different species of viruses.

Common

What is in the core of a virus?

DNA or RNA

Once a prophage cell is activated, what happens?

DNA starts replicating, host cell enters lytic cell.

T-phages often attack what bacterial cell? Where is the host cell found?

E.coli, in the intestines

Besides smallpox and AIDS, name 6 other viral diseases.

Ebola, Influenza (flu), Herpes, Mumps, Shingles, Viral pneumonia

Who found the vaccine against this viral disease? What milder virus was used to make the vaccine?

Edward Jenner, he used milder cowpox viruses

_________ infections also remain dormant in the nervous system.

Eukaryotic Virus

Give an example of a retrovirus.

HIV and AIDS

What discovery did Geisbert make about the viruses infecting the monkeys?

He discovered that it was a filovirus, or a threadlike virus. He had thought it was marburg.

How did Delgard ship the results of the monkey autopsy to Jahrling?

He sent them in aluminum foil and not in safe conditions because the blood had seeped into the ice in the cooler.

Describe Jahrling's tests with the virus samples.

He used the blood serum from human victims of Marburg, Ebola Sudan, and Ebola Zaire and watched to see how they would react to the virus in the monkey cells. If the serum glowed, that meant that the human victim's virus was similar to the monkey virus because the serum recognized it.

Who is C.J. Peters?

He was the chief of the disease-assessment division of the Institute who dealt with unknown dangerous viruses.

Who is Dan Delgard?

He was the consulting veterinarian at the Reston Primate Quarantine Unit. He took care of the monkeys if there were sick or needed medical attention

Who is Tom Geisbert?

He works at the institute photographing pictures of viruses on an electron microscope. He was the one who discovered the filovirus in the monkey's cells.

What virus causes blisters that may appear around the mouth?

Herpes

Give the family, genus, and species for the HIV and Herpes viruses.

Herpes, Herpesviridae, Herpesvirus, Human Herpesvirus 1, HHV 2, HHV 3; HIV, Retroviridae, Lentivirus, Human Immunodeficiency Virus 1, HIV 2

What is the envelope of viruses often made from? What is the function of an envelope?

Host cell membrane, envelopes protect the virus.

Do the viruses that attack most animals also attack most humans?

Humans rarely share diseases with other animals.

What is meant by a "chain of command" in relation to biohazard work?

In General Russell's opinion, the job of dealing with the virus in Reston was a job for soldiers working under a chain of command because they needed people trained in biochemical work.Also, it could mean that the Institute didn't have the first authority to go and wipe out the virus, they had a chain of command on who could work on the situation.

What virus is responsible for the common cold?

Influenza

How are some viral vaccines made?

Interferon (naturally occurring proteins made by cells to fight off viruses), genetic altering, Antiviral drugs, and Protease inhibitors.

Viroids resemble ______ pieces of DNA that are cut out because they do not code for any proteins.

Introns

How does an attenuated virus help protect us from disease?

It stimulates an immune response and creating immunity but not causing illness.

Who is Jarvis Purdy? What happened to him?

Jarvis Purdy is one of the four workers in the monkey house. Purdy had a heart attack, he was sent to the hospital and his condition was guarded but stable.

Viruses make us sick because they ____ healthy host cells.

Kill

Name a type of cancer thought to be caused by viruses.

Leukemia

Viruses only attack

Living host cells.

How long can a latent virus remain inactive?

Long periods of time (years)

Who coined the term virus and what does it mean?

Martinus Beijerinck and it means a biological agent that reproduces inside the cells of living hosts

What metric units are used to measure the size of viruses?

Micrometer (nanometers)

Does the prophage start replicating right after it is injected into the host cell? Explain.

No, it may stay inactive for a long period of time.

Do prions have a nucleic acid core?

No, they don't have DNA or RNA

Define virus.

Non Cellular particle made up of genetic material and proteins that invade living cells.

Can viruses be "killed"?

Not killed but destroyed because they are not technically alive. They can be crystallized, or heated

What virus causes warts?

Papillomavirus

What is the host for viroids?

Plant cells.

Viroids are responsible for causing what major problem in Europe?

Potato Famine.

What protein is responsible for most mammalian prion diseases?

PrP

Explain the prion disease caused kuru.

Prions that were miss-folded and are responsible for destroying brains

How do protease inhibitors work to stop viruses?

Protease inhibitors are antiviral drugs. They interrupt the way HIV uses a healthy cell to make more virus. When HIV enters a healthy cell, its only goal is to make more viruses to infect other healthy cells. It does this by making the cell produce certain proteins the virus can use to copy itself.

Describe the capsid of viruses.

Protein coat that surrounds the viral genome

Prions are infectious pieces of _______.

Proteins

Name the 2 main things that make up a virus.

Proteins and nucleic acid and proteins

Name 4 things used to identify viruses.

RNA OR DNA VIRUS, DO OR DO NOT HAVE AN ENVELOPE, CAPSID SHAPE, HOST THEY INFECT

What 2 things do retroviruses inject into their host cells when they attack them?

RNA and reverse transcriptase enzymes

What nucleic acid do retroviruses contain?

RNA not DNA

What enzyme do retroviruses contain that let them make DNA from RNA?

Rtase or reverse transcriptase

This virus may reappear later in life as a disease called _shingles___. Describe the disease.

Shingles is a painful, itchy rash that is limited to small areas of the body.

How does a bacteriophage attach to its host cell?

Six small spikes at the base of a contractile tail are used to attach to the host.

What is a viroid?

Small, circular, RNA molecules, without a protein coat

what activates latent viruses?

Some external signal

What protective covering is around the capsid of some viruses?

Spikes

What are capsomeres?

Subunit of the capsid, an outer covering of protein that protects the genetic material of a virus.

What are the most commonly studied T-phages

T4 and T7

What were the results of these tests?

The Ebola Zaire serum glowed which meant that the disease was either Ebola Zaire or something similar.

What structures help a virus attach to a host cell?

The capsid, and spikes

Who is Joe McCormick?

The chief of the Special Pathogens branch at the C.D.C.

What technology had to be developed before viruses can be seen?

The electron microscope

What is the purpose of spikes and do all viruses have them?

The purpose of spikes are to help attach to the host cell, not all cells have them

What were the results of the monkey autopsy?

The spleen was puffed up and tough, it did not bleed into itself, there was no blood in the intestines, there were bleeding spots in the inside of the stomach and intestines, she couldn't tell that the monkey had definitely died of Ebola based on that autopsy.

During the lysogenic cycle of a virus, what happens to the viral nucleic acid after it is injected into the host cell?

The viral DNA joins host DNA forming a prophage. When an activation signal occurs the phage DNA starts replicating.

What significant event occurred over the Thanksgiving holiday in the monkey house?

The virus had traveled to another room and was spreading quickly through the building. It had skipped one room and gone to the next room over.

Describe the conditions of the monkey house upon the team entering the building.

The whole building smelled of monkey, and the workers had stopped cleaning the cages. They didn't want to go back to the monkey's room because of the hot agent.

Describe the deaths of the monkeys.

Their livers become a giant blood clot and they die of liver failure. Their faces become very passive and their eyes droop.

How are viruses attenuated?

They are heated

Describe how prions occur.

They are natural proteins that get converted into an alternate configuration

Are all viruses the same shape?

They are not all the same shape

What does the virus inject into its host?

They inject their nucleic acid

Do viruses have enzymes like cells?

They lack enzymes

What was the purpose of the conversation between Jahrling and Geisbert? (see page 206.)

They talked about how they had whiffed the flask of potentially infected monkey cells and could have contracted the disease.

What kinds of monkeys were kept at the Reston Monkey House?

They were crab eating monkeys from Southeast Asia

How were the dead monkey's shipped to Fort Detrick?

They were dropped off at a gas station and picked up by people working at the Institute, they were double bagged and soaked outside the bags with Clorox bleach. Then, they were taken by car to Fort Detrick in C.J.'s truck.

What is the only part of the virus that actually enters the host cell?

Viral DNA

What is meant by a virulent virus?

Virulent viruses are deadly

Are viruses made of cells? Are they living?

Viruses are not made up of cells, non living structures

How does the size of a virus compare with that of a cell?

Viruses are smaller than the smallest cell

Can a virus maintain homeostasis like cells?

Viruses do not maintain homeostasis.

Are viruses cellular or noncellular?

Viruses have noncellular particles made of protein that may invade living cells.

Viruses are host specific. What does this mean?

Viruses only attack specific species, and rarely crossing species.

What are latent viruses?

Viruses that can become dormant inside the cell

Why might some people consider viruses alive?

When they infect a host they gain properties of a living organism such as being able to reproduce.

Does the HIV virus have spikes for attachment?

Yes

What is AZT?

an anti-HIV drug that reduces the amount of virus in the body.

Viral DNA along with the host cell DNA is replicated during each

binary fission_.

What is the shape of the bacterial host cell that bacteriophages attack?

icosahedral

Give 3 characteristics of T-phages.

icosahedral heads , Double stranded DNA, Tails

Once a prophage is active, the host cell is ______________ making the virus deadly or _______________.

lyses, virulent

After a long period of time, ________ cells form that contain ________________.

many, prophages

What are the head and tail fibers made of?

protein

Viruses use the ________ and _______of its host cell to be able to reproduce

raw materials and enzymes

Genital herpes is called Herpes ________, while cold sores or fever blisters are known as Herpes ____.

simplex 2, simplex 1