Viruses Flashcards
What are two biochemical components of viruses
1)Protein coat
2)nuclei acid (DNA or RNA)
Are viruses cellular
They are non cellular
How do scientists classify viruses?
Classified on shape
What type of shapes do viruses have?
1)spherical
2)rod-shaped
3)complex shaped
What term is used for viruses of how they reproduce
Replication
Why are viruses known as obligate parasites?
Require a host player to replicate
Give an example of a obligate parasite
Bacteriophage that infects bacteria
What are the stages of virus replication
1)attachment
2)entry
3)synthesis
4)assembly
5)release
How many stages are there in virus replication
5
What is attachment in virus replication?
Attach to cell membrane
What is entry in virus replication?
Nucleic acid pushed through
What is synthesis in virus replication?
Uses host cells to produce new nucleic acid and protein coats
Is assembly in virus replication?
Protein coat with a nucleic acid form new viruses
What is release in virus replication?
Host cell bursts
Why are viruses not assigned to any the five kingdoms of life?
As they are not considered to be living
1)they are non cellular
2)require host cell to replicate
3)only one type of nucleic acid (DNA or RNA)
Why viruses can be classified as living?
1)they have nucleic acid
2)can replicate
3)protein coat
Why can viruses be classified as non living?
1)They are non cellular
2)host cell can replicate
3)one type of nucleic acid
A virus can be described as a piece of genetic material that has escaped from a cell. Give one piece of evidence
Contain nucleic acid
What the benefits of economic and medical importance of viruses?
1)medical-produce vaccines
2)genetic engineering-used as vectors
3)control of infections-control bacterial infections
What are the disadvantages of economic and medical importance if viruses?
Pathogens and can cause disease
1)human diseases
2)animal diseases
3)plant disease
Give examples of human disease?
1)AIDS
2)common cold
Give examples of animal diseases
1)Foot and mouth disease
2)rabies
Give an example of plant diseases
1)Tobacco mosaic disease
What abbreviation does HIV stand for?
Human immunodeficiency virus
What abbreviation does AIDS stand for?
Acquired immune deficiency syndrome
What term is used for how AIDS or HIV get into a person
Transmission
How does HIV or AIDS get into a person?
§)Blood or semen
2)across the placenta or in breast milk
What are the effects of the HIV virus
Enters a white blood cell
1)remain dormant can be identified as HIV positive
2)breaks down white blood cell and cannot produce any antibodies
3)resistance of infection is reduced
What occurs to the antibodies in HIV ?
Antibodies don’t work
What occurs when a AIDS person when they get a infection
Can die from common infections
What is the prevention and control for HIV and AIDS
1)avoidance of intercourse so remain faithful to partner
2)using a condom
3)don’t use shared needles
4)should not donate blood
If there a cure for AIDS
No cure or vaccine
AIDS had orphaned many children in sub-Saharan Africa due to?
1)lack of education
2)cultural/religious reasons
3)lack of healthcare
What is foot and mouth diease?
Affects animals with split hooves
How is foot and mouth disease transmitted?
Contact with infected animals or with vectors
What are the effects of foot and mouth disease?
1)Blisters in the mouth and hooves
2)Lost of weight, milk or wool
How to prevent and control foot and mouth disease?
1)Animals killed and burnt
2)spread the disease can be prevented by keeping an area under quarantine
How are viruses killed or controlled?
1)body’s immune system
2) lymphocytes produce antibodies
