viruses Flashcards
what are viruses
They are simple, acellular entities of one or more molecules of DNA or RNA not both and are enclosed in a coat of protein, lipids or carbohyratesand can only reproduce in living cells- obligate intracellular parasites
examples of airborne disease
chickenpox, shingles, germen measles (rubella) and influenze
examples of arthropod borne disease
yellow fever arbovirus
examples of direct contact diseases
AIDS, cold sires, common cold, genital herpes, rabies and hepatitis
examples of food-borne diseases
polio and infectious hepatitis
examples of other virueses
warts, verucas, HPV
what is the geonme of a viruse
RNA or DNA, double or single stranded, segmeted or non-segmented
what is the compoisition of the envelope
lipids from host cell membrane, proteins and glycoproteins
what is the function of the enevlope
camoflage and recognition and attachment to host cell
what are capsids
the proteins forming the virus shell. they are rings
what is verial shape
helical or isometric (cubic). the number of protein molecules in the virus are large but rarely more than one
what are icosahedral capsids
form ring shape units called capsomeres- 5 or 6 protomers
explain the classification of viruses
host range= very specific, but can jump between species through mutations
envoloped or non
type of nucleic acid= single or double
shape= different shapes
what is the size of viral shape
10-500nm and 1000 microletersin a naometre
what is icosahedral
polyhedron with 20 triangular faces