Micro Bio Exam 3

Chapters 4, 12, 13 & 14

Viruses charactersitics

contains DNA or RNA; have protein coat; must have a host cell; uses metabolic machinery of host

host range

specific viruses have requirements for attachment and the availability of cellular factors in a host for viral multiplication

how do viruses infect?

they must chemically interact with the receptor on the cell

oncolytic virsuses

selectively infect and kill tumor cells; form of cancer imunotherapy

phage therapy

use of viruses to treat bacterial infections

how to see viruses

through electron microscopy

capsid

protein coat that protects the nucleic acid

envelope

an additional layer to the capsid that is a combination of lipids, proteins, and carbs; in some but not all virsues

spikes

carbs projecting from the surface; may or may not cover the envelope

viruses nucleic acids

DNA or RNA (not both)

hemagglutination

the clumping or agglutination of red blood cells

coagulation

the formation of a solid, insoluble mesh of fibrin, platelets, and rbcs

helical viruses

long rods within a cylindrical capsid that has a helical structure

polyhedral viruses

many-sided

icosahedron

a category of polyhedral viruses and have 20 triangular faces and 12 corners

enveloped viruses

roughly spherical enclosed by an envelope

complex viruses

especially bacterial viruses and have other attachments to the capsid