Micro chapter 13
Card Set Information
Micro chapter 13
protein coat around the nucleic acid core of a virion
capid + virion
phospholipid membrane on outside of the capsid; protects and helps gain entry
into animal host cell.
intracellular; consists of just the nucleic acid core.
What is an extracellular virus called?
How are viruses classified?
By the type of genetic material they contain, the size and shape of the virus, and the
presence or absence of an envelope.
Know the different forms of nucleic acid that a virus may contain (sRNA etc.)
dsDNA; dsRNA; ssDNA; ssRNA
Be able to describe the steps in viral replication
Compare the differences in animal virus and bacteriophage replication.
Animal viruses attach using glycoprotein spikes on their capsid or envelope.
All animal virus capsids have to be removed if the capsid enters the host cell.
Be able to describe and compare lytic cycle and lysogeny.
Lytic cycle- synthesis occurs right after vision enters the cell.
Lysogeny- virion remains in the cell for several cellular reproductions before synthesis is
A virus is called a ______ when its DNA becomes incorporated into an animal host’s
A virus is called _________ when its DNA become incorporated into a bacterial host's
the prophage genome is released from the bacteria genome. usually the same chemical or physical agents that can cause damage to DNA
Understand the connection between HIV and retroviruswes
Both viruses infect specific cells in their hosts. HIV- T lymphocytes in humans.
Retroviruswes- brain cells of animals and humans.
Explain how viruses can cause cancer
Viruses may cause cancer by carrying copies of oncogenes to other cells, promoting
oncogenes already present in a cell, or by interfering with genetic expression when they are
acting as proviruses.
uncontrolled growth from a change in a gene
mass of neoplastic cells
Be able to explain the difference between oncogenes and proto-oncogenes
proto-oncogenes- genes for cell division that are turned off when cell division is not
oncogenes- causes tumor cells
Be able to explain the difference between viroids, prions and viruses.
Viroid- do not have a capsid; infect plants
Virus- infect animals, have a capsid.
prions- protein, infect the brain.
Know the structure of prions and viroids and what they infect.
Viroids- tiny, circular pieces of infectious RNA; appear linear. Infect plants.
Prions- protein, Beta pleated form of PrP; infect the brain.