Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
21 Cards in this Set
- Front
- Back
|
Viruses |
-Contain a single type of nucleic acid (DNA or RNA) -Have a protein coat -multiply inside living cells by using the synthesizing machinery of the cell -only obligatory intracellular parasites |
|
|
Bacteria |
-have both DNA and RNA -most have cell wall -some multiply by binary fusion -some obligatory intracellular parasites but others can live freely as decomposers, photosynthetic, chemosynthetic |
|
|
Most significant evidence that supports this idea that viruses are non-living |
Nucleic acids are inactive outside of living host cells; cannot live on its own=ie. obligatory intracellular parasite; cannot multiply outside of a living host |
|
|
Life Style of viruses |
Obligatory intracellular parasites; host range= wide (bacterial, plant, animal) |
|
|
Structure of viruses |
Small in size; SPECIFIC= host specific - dependent on specific receptors; contain DNA or RNA
|
|
|
Are cell walls present in viruses? |
No, they are absent |
|
|
Are protein coats present in viruses? |
Yes, they are always present |
|
|
Are envelopes present in viruses? |
Yes, they are found in some |
|
|
Are DNA and RNA present in viruses |
either one or the other, not both |
|
|
Are spikes present in viruses |
Yes, they are found in some; used for attachment and identification |
|
|
What shapes can viruses be in |
Helical, Polyhedral, or complex |
|
|
What are different methods used for culturing viruses |
Viruses are cultivated in: Living animals, embryonated eggs, and in cell cultures |
|
|
Why is laboratory culture media not used for culturing viruses |
Viruses cannot grow in lab media |
|
|
why are continuous cell lines more practical than primary cell lines for culturing viruses? What is the difference between continuous cell lines and finite cell lines? |
continuous cell lines can be maintained through an indefinite number of generations (Immortal cell lines), which allows for lots of virus culturing. Primary cell line, on the other hand, tend to die out after only a few generations. If the cell isn't living, the virus can't either Continuous cell lines=used for propagation- grows immediately Finite cell lines= die out after only a few generations; used to study cell deterioration= cytopathic effect (CPE) |
|
|
What are the different criteria used to classify viruses |
classification is based on -the type of nucleic acid (DNA or RNA) as DNA viruses or RNA viruses -#of nucleic acid strands, whether it is single-stranded or double-stranded -Whether the virus is enveloped or naked |
|
|
Why are the biochemical tests not used for purpose of classification of viruses like it is done for bacteria |
Biochemical tests are not used for the purpose of classification/identification because viruses do not produce enzymes that can perform the specific function needed for identification (they use the host's) |
|
|
What is the chemical composition of spike |
Protein and carbohydrate complex |
|
|
What is the chemical composition of envelope |
Protein, carbohydrate, and fat |
|
|
Is an envelope or a spike used as an identification tool and what test is used for the purpose of identification |
The spikes are used for identification. The specific test is the serological tests which is used for identification |
|
|
What is the most practical method for identification of viruses in clinical laboratory |
1) Serological methods are the most common used means of identification - the virus is detected and identified by its reaction with antibodies 2)Cytopathic effects are also used to identify/classify viruses 3)Nucleic acid base sequencing |
|
|
What is the method for identification of bacteriophages in the lab? What is a clear are against confluent "Lawn" of bacteria |
The method for identifying bacteriophages in the lab is called the plaque method. The clear area against a lawn of bacterial growth is known as plaque |
