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Published byEthel Jennings Modified over 6 years ago
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Viruses Viruses – particle made up of nucleic acid (DNA or RNA), protein, and in some cases lipids that can replicate only by infecting living cells Core of DNA or RNA surrounded by protein coat (capsid), some look like little spaceships
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Herpes Herpes virus
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Viruses are not alive 1) They do not maintain homeostasis
3) They do not grow. 4) They do utilize energy on their own. 5) They do not reproduce on their own. 6) They are not made of cells. Although they DO have DNA and RNA
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Viruses are TINY
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Bacteriophage – virus that infects a bacteria
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Replicative Cycles Cannot reproduce on own.
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C. Lytic Infection 1. Virus enters cell 2. Makes copies of itself
3. Causes cell to burst
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Lysogenic Infection Review
- Virus embeds its DNA into the DNA (genome) of the host cell & is replicated along with the host DNA Then after numerous cell divisions acts like lytic infection and bursts cells
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Viruses and Disease Examples: polio, rabies, measles, AIDS, mumps, influenza, yellow fever, & common cold
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Viruses and Disease Best human protection: vaccines: injection with weakened virus that triggers human immune system to make antibodies.
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Herpes Simplex ( cold sore)
65% of Americans carry this virus Changing conditions (stress, heat, etc.) can bring about lytic cycle Kiss me, my valentine!!
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