You are in browse mode. You must login to use MEMORY

level: Level 1 of Chapter 2 - Viruses

Questions and Answers List

level questions: Level 1 of Chapter 2 - Viruses

Question	Answer
• Distinguished from other infectious agents as very small and filterable	VIRUSES
General Characteristics OF Viruses	1 Obligatory Intracellular parasites 2 Contain a single type of nucleic acid 3 Contain protein coat that surrounds the nucleic acid 4 Multiply inside living cells by using the synthesizing machinery of the cell 5 Cause the synthesis of specialized structures that can transfer the viral nucleic acid to other cells. 6 Few or no enzymes for their own metabolism
There are __ number of antiviral drugs developed a. few b. many	a. few It is difficult to create a drug which does not interfere with the normal functioning of the host cell which viruses use as machinery
Viruses contain plasma membrane	No
Viruses are what type of parasites?	Intracellular parasites
Can viruses pass through filters?	No Too small size
Viruses contains both DNA and RNA	No, they either have DNA or RNA only
Are viruses sensitive to antibiotics?	No Only Antiviral works
Are viruses affected by interferons?	Yes They are proteins secreted by the immune system to fight viruses
Naturally occurring proteins that are made and secreted by the cells of the immune system.	Interferons
• For the virus to infect cell, the outer surface of the virus must what?	Chemically interact with the specific receptor sites of the cells If achieved, it will be held by hydrogen bond
• When infected with a virus, the host’s immune system is stimulated to produce what?	Antiodies
• Proteins that interact with the surface protein of the virus • These interactions will either inactivate or stop the infection	Antibodies
• Viruses genes are susceptible to what?	Mutation Help them escape antibodies
Receptor sites of bacteria is found on	• The cell wall, fimbriae, or flagella.
Receptor sites for animals or humans is found on	• Plasma membrane
• Viruses that infect bacteria	Bacteriophage
Viral size of viruses	• 20 to 1000 nm in length can be determined by electron microscope
a complete, fully developed infectious viral particle which is composed of nucleic acid serves as a vehicle for transmission from one host cell to another	Virion
• Can be linear, circular, or in separate segments • single or double stranded	Nucleic acid
What are the structures of Virion?	1 Nucleic acid 2 Capsid 3 Envelope