Lesson 5 Flashcards
Complete virus particles
Virions
Most virus ranges in size from ______ to ______ nm in diameter
10-300
What microscope were used to see viruses
Electron microscope
Electron microscope were in invented in
1930s
First photograph of viruses were obtained in
1940
Are all organisms safe from viruses
No
Viruses that causes specific types of cancer, including human cancers such as lymphomas, carcinomas, and some types of leukemias
Oncogenic viruses / oncoviruses
Give specific properties of viruses
They possess either DNA or RNA
They are unable to replicate on gheir own
They do not divide by binary fission, mitosis, or meiosis
The protein coat
Capsid
The nucleic acid and the capsid are referred to as
Nucleocapsid
Many small protein unit
Capsomeres
Have an outer envelope composed of lipids and polysaccharides
Enveloped viruses
Viruses are classified by what?
- Type of genetic material
- Shape of the capsid
- Number of capsomeres
- Target cells
- Type of diseases it produces
It is derived from either the host cell nuclear membrane or cell membrane
Envelope
Two theories of origin of viruses
Viruses existed before cells
Cells came first
They are referred to as acellular microbes or infectious particle
Viruses
Viruses are referred to as _____ or ______
Acellular microbes or Infectious particles
Are viruses considered as living organisms?
No
Viruses that infect bacteria
Bacteriophages
Theee categories of bacteriophages
Icosahedron bacteriophages
Filamentous bacteriophages
Complex bacteriophages
A bacteriophages with an almost spherical shape; with 20 triangulat facets
Icosahedron bacteriophages
A bacteriophages which icosahedral head attached to helical tails
Complex bacteriophages
A bacteriophages which long tubes formed by capsid proteins assembled into a helical structure
Filamentous bacteriophages
It is known as the lytic cycle
Virulent bacteriophages
It ends with the destruction of the bacterial cell
Virulent bacteriophages/ lytic cycle
What are the STEPS in the Lytic Cycle
APBAR
Attachment
Penetration
Biosynthesis
Assembly
Release
Lytic cycle: the phage injects its DNA into the bacterial cell
Penetration
Lytic cycle: the phage genes are expressed, resulting in the production of viral pieces
Biosynthesis
Lytic cycle: the viral pieces are assembled to produce complete viral particles
Assembly
Lytic cycle: the host cell bursts open, and all of new virions escape from the cells
Release
Also known as lysogenic phase
Temperate phages
They do not immediately initiate lytic cycle, but rather their DNA remains integrated into the bacterial cell chromosome, generation after generation
Temperate phages or lysogenic phages
Viruses that infect human and animals are collectively referred to as
Animal viruses
Steps in multiplication of animal viruses
Attachment
Penetration
Uncoating
Biosynthesis
Assembly
Release
Steps in multplication of bacteriophages
Attachment
Penetration
Biosynthesis
Assembly
Release
Steps in multiplication of animal viruses whereby “the viral nucleic acid escape from the capsid”
Uncoating
Steps in multiplication of animal viruses wherein “after the virus particles are assembled, they must escape from the cell”
Release
It is known as cold sores / fever blisters
Herpes virus infections
A good example of latent virus infections
Herpes virus infections
A painful nerve disease that is also caused by herpes virus
Shingles
It is prescribed in an attempt to prevent secondary bacterial infections that might follow the virus infection
Antibiotics
It it developed to interfere with virus-specific enzymes and virus production
Anti-viral agents
Viruses that causes cancer
Oncogenic viruses / oncoviruses
The first evidence that viruses cause cancers came from experiments with _________
Chicken
A type of herpes virus that causes mononucleosis
Epstein-Barr Virus
A type of cancer common in AIDS patients, caused by human herpes virus
Kaposi sarcoma
It cause cancers of the cervix and other parts of thr genital tract
Human Papilloma Virus (HPV)
Known as wart viruses
HPV
The cause of Acquired Immune Deficiency Syndrome / AIDS, is an enveloped single stranded rna virus
HIV / human immunodeficiency virus
Extremely large double stranded DNA virus
Mimivirus
Mimivirus has been recovered by?
Amoebas
It mimics bacteria
Mimivirus
Infectious RNA molecules that cause a variety of plant diseases
Viroids
Infectious protein molecules that cause a variety of animal and human diseases
Prions
A disease where women and children ate human brains as part of a traditional burial custom
Kuru
Kuru is common among natives in?
Papua, New Guinea
A general mental deterioration, characterized by disorientation and impaired memory, judgment and intellect
Dementia
Example of prions diseases
Kuru
Mad cow disease
C-J disease
