Chapter 6 microbiology

Rank the following viruses from smallest to largest

1. Yellow Fever 2. Phage T2 3. Influenza 4. Herpes 5. Poxvirus 6. Megavirus

The capsid of a viral particle is composed of identical proteins called ____

Capsomers

Reovirus Cytopathic effect

Cell enlargement

Rabies virus cytopathic effect

No change in cell shape

___ viruses can infect host cells and later lead to cancer

oncogenic

True or false The hepadnavirus family is so named because viruses within the family infect the liver and possess DNA as their genetic material.

True

True or false The viral host relationship is extremely important for pathogenicity, mode of transmission, the immune response, and the human measures used to control viral infections

True

True or false Viral nuclei acid enters the host cell and uses the host cells replication and synthesis machinery in order to produce new nucleic acid molecules, proteins for the capsid, spikes, and viral enzymes

True

penetration stage of viral replication

Virus is engulfed in a vesicle or endosome and transported internally

Which of the following characteristics are associated with transformed cells?

altered chromosomes changes in cell surface molecules integration of viral DNA into host chromosome

Please select all of the following that represent viral characteristics

are obligate intracellular parasites have a 20 to 450 nanometer diameter are composed of a capsid surrounding a nucleic acid core

Cytopathic changes in virally infected animal cells include

inclusions in the cytoplasm clumping of cells cell lysis cytoplasmic inclusions formation of multinucleate syncytia

True or false The light microscope was critical in the discovery of the viruses

False

Viruses first appeared on Earth sometime after the rise of eukaryotic organisms.

False

Measles virus Cytopathic effect

Formation of syncytia cell fusion?

What data or achievement was instrumental to the initial characterization of viruses?

the discovery that infectious fluid remained infectious even when passed through a filter designed to trap bacteria

Together, the capsid and the nucleic acid are referred to as the _____.

nucleocapsid

All viruses

possess a capsid composed of protein are reliant on a host cell for their own reproduction

The special affinity that a virus has for a particular type of tissue is called a __________.

tropisms

Fully formed viral particles capable of establishing infection in a new host are called ____

virions

adenovirus cytopathic effect

Clumping of cells

virus-induced damage to the host cell, called ____ effecta, can include changes in the cell size and shape

Cytopathic

Select all of the statements that are true regarding penetration of animal viruses

Enveloped viruses can penetrate by fusion, Enveloped viruses can penetrate by endocytosis, Nonenveloped viruses can penetrate by endocytosis, Once inside the host, viruses become uncoated.

True or false The envelope is entirely formed from the viral material

False

True or false Viral replication follows essentially the same steps as prokaryotic cells

False

True or false Virus are classified into species based on whether they can reproduce to produce fertile offspring, much like plants and animals

False

Which of the following are the most useful using modern system to classify a newly discovered virus?

Genome RNA, envelope contains particular spike proteins, Capsid is isosahedral

Regarding replication of an enveloped animal virus, match the stage of replication with its definition.

Release, synthesis, adsorption, penetration, assembly, uncoating

helical capsid

Rod-shaped capsomeres that bind together too resemble a bracelet

Influenza Cytopathic effect

Rounding up of cells

Feline leukemia virus may be lethal to cats but does not infect humans. This is a reflection of

The host range of feline leukemia virus

Which of the following are true about viral envelopes

They are composed of host membrane, They can contain host-encoded proteins, They can contain virus-encoded proteins, They are important for binding to host cells.

icosahedral capsid

Three-dimensional, 20-sided figure with 12 evenly spaced corners

Please select the characateristics that are used to identify and name viruses

Type of capsid, Type of envelope, Nucleic acid strand number, Area of rhe host cell in which the virus multiplies

Synthesis Stage of viral replication

Under control of viral genes, the host cell synthesis all the components needed to assemble new viral particles

Uncoating stage of viral replication

Vesicle membrane and viral envelope fuse, releasing capsid into the host cytoplasm

poliovirus cytopathic effect

cell lysis; no inclusions

What is the true concerning the viral envelope ?

It contains viral proteins, It was once a part of the host cell.

Which of the following terms is associated with the release of nonenveloped or complex viruses from the host cell?

Lysis

release stage of viral replication

Viruses bud of from the host cell membrane

Assembly Stage of viral replication

Viral nucleic acid encased in capsid, viral proteins inserted in host cell membrane

The "Adsorption" stage of the viral replication cycle involves

Virus attached to its host cell by binding cell surface receptors