virus what am i?. virus what am i? virus what am i?
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Virus
What am I?
Virus
What am I?
Virus
What am I?
Virus
What am I?
Virus
What am I?
Virus
How do I spread?
Virus
How do I spread?
Virus
How do I spread?
Virus
How do I spread?
Virus
How do I spread?
Virus
What is my relationship between human behavior and me?
Virus
What is my relationship between human behavior and me?
Virus
What is my relationship between human behavior and me?
Virus
What is my relationship between human behavior and me?
Virus
What is my relationship between human behavior and me?
Virus
What is my relationship between human behavior and me?
Virus
What is my relationship between human behavior and me?
What do you know about viruses?
• Think– About
the questions
• Pair– Talk to your partner
about the answers.
• Share• Share with
the class
What is a virus?
How do I spread?
What is my relationship between human behavior and me?
Video
• Identify three new ideas about viruses
http://209.68.130.2/videos/qt/300k/1_3161_300k.mov
New Questions you need answered.
• As you read, open to address below and add your questions to “Web Response”
• http://PollEv.com• Or
– Add your questions to post it notes.
QAR Strategy• Right There:
– What is vomito Negro?
• Think and Search:– What is the pattern of the virus’s effect on the body?
• Author and you:– How does Monet’s experience in the emergency room
relate to your own experiences in an emergency room or some other time when you needed swift attention?
• On Your Own:– If you were seated next to a passenger with these
symptoms, what would you do?
E.coli and T4 phage
Virusbook
Taking advantage of our social network
Waiting for a flight
Procedures
• You must wear goggles at all times.• Day 1:
– Find a person from a different table.1. Ask each other a question about the story.
2. Exchange 1 ml of water, if they did not know the answer, and ½ of ml of water if they did know the answer.
3. Find another person and ask another question.
4. Return to your desks and write down the names of the people you met.
Procedures
• You must wear goggles at all times.• Day 2:
– Find a person from a different table.1. Ask each other a question about the story.
2. Exchange 1 ml of water, if they did not know the answer, and ½ of ml of water if they did know the answer.
3. Find another person and ask another question.
4. Return to your desks and write down the names of the people you met.
Infection
Did you contract the virus
• One person in the Waiting room had the filovirus.– Who had it?– Did you have contact with that person?– Did you have contact with that person
indirectly?– How can we be sure who has the virus?
Classify the questions
Right There Think and Search Author and You On Your Own
Search
• Pg 37-38; 62-67; 83-86; 98-100; 105-109; 117-118; 197-198
• http://www.cdc.gov/ncidod/dvrd/spb/mnpages/dispages/ebola.htm
• http://www.biology.arizona.edu/cell_bio/tutorials/pev/page4.html
• 82-84; 121-129; 153-157; 174-178; 185-192; 204-206; 323-325
Science @ Home
• Email me tonight your answersjorlinsky@dusd.net
1. What is a virus?
2. How do they spread?
3. How does human behavior affect the spread of viruses.
4. one question from the Classify QAR
Read 215-17 & 360-371
• Right There– What other ways can filovirus spread?
• As you read…– Develop questions:
• Think and Search• Author and you• On Your Own
Read 350-354 & 567-584
EBOLA POSTER
• You will make a Ebola virus prevention poster.– It must include.
• Very few words, • Pictures showing how to prevent the spread of the
virus.
– It should not scare people, but be informative.
Structure
• 20 nm• Genomes
– Ds DNA (Papo, adeno, herpes, pox)– Ss DNA (Parvo)– Ds RNA (reovirus)– Ss+ RNA (pico and toga) – SS- RNA (Rhabdo,Paramyxo, Ortho)– Retrorivus ss RNA
Structure
• Capsids– Protein coats– Phages
• Some viruses have structures have membranous envelopes that help them infect hosts
• These viral envelopes surround the capsids of influenza viruses and many other viruses found in animals
• Viral envelopes, which are derived from the host cell’s membrane, contain a combination of viral and host cell molecules
Structure
LE 18-4c
Glycoprotein
80–200 nm (diameter)
RNA
Capsid
Influenza viruses50 nm
Membranousenvelope
• Bacteriophages, also called phages, are viruses that infect bacteria
• They have the most complex capsids found among viruses
• Phages have an elongated capsid head that encloses their DNA
• A protein tailpiece attaches the phage to the host and injects the phage DNA inside
LE 18-4d
80 225 nm
DNAHead
TailsheathTailfiber
Bacteriophage T450 nm
LE 18-5
DNAVIRUS
Capsid
HOST CELL
Viral DNA
Replication
Entry into cell anduncoating of DNA
Transcription
Viral DNA
mRNA
Capsidproteins
Self-assembly ofnew virus particlesand their exit from cell
Reproduction
Class/Family Envelope Examples/Disease
I. Double-stranded DNA (dsDNA)
Adenovirus No Respiratory diseases, animal tumors
Papovavirus No Papillomavirus (warts, cervical cancer): polyomavirus (animal tumors)
Herpesvirus Yes Herpes simplex I and II (cold sores, genital sores); varicella zoster (shingles, chicken pox); Epstein-Barr virus (mononucleosis, Burkitt’s lymphoma)
Poxvirus Yes Smallpox virus, cowpox virus
Class/Family Envelope Examples/Disease
II. Single-stranded DNA (ssDNA)
Parvovirus No B19 parvovirus (mild rash)
III. Double-stranded RNA (dsRNA)
Reovirus No Rotavirus (diarrhea), Colorado tick fever virus
Class/Family Envelope Examples/Disease
IV. Single-stranded RNA (ssRNA); serves as mRNA
Picornavirus No Rhinovirus (common cold); poliovirus, hepatitis A virus, and other enteric (intestinal) viruses
Coronavirus Yes Severe acute respiratory syndrome (SARS)
Flavivirus Yes Yellow fever virus, West Nile virus, hepatitis C virus
Togavirus Yes Rubella virus, equine encephalitis viruses
Class/Family Envelope Examples/Disease
V. ssRNA; template for mRNA synthesis
Filovirus Yes Ebola virus (hemorrhagic fever)
Orthomyxovirus Yes Influenza virus
Paramyxovirus Yes Measles virus; mumps virus
Rhabdovirus Yes Rabies virus
VI. ssRNA; template for DNA synthesis
Retrovirus Yes HIV (AIDS); RNA tumor viruses (leukemia)
Other Issues
• HIV and AIDS• Viruses and Cancer• Vaccines• Plant Viruses• What’s New
LE 18-9
Capsid
Viral envelopeGlycoprotein
Reversetranscriptase
RNA(two identicalstrands)
• The viral DNA that is integrated into the host genome is called a provirus
• Unlike a prophage, a provirus remains a permanent resident of the host cell
• The host’s RNA polymerase transcribes the proviral DNA into RNA molecules
• The RNA molecules function both as mRNA for synthesis of viral proteins and as genomes for new virus particles released from the cell
LE 18-10
HOST CELL
ReversetranscriptionViral RNA
RNA-DNAhybrid
DNA
NUCLEUS
ChromosomalDNA
Provirus
RNA genomefor thenext viralgeneration
mRNA
New HIV leaving a cell
HIV entering a cell
0.25 µm
HIVMembrane ofwhite blood cell
Viral Diseases in Plants
• More than 2,000 types of viral diseases of plants are known
• Some symptoms are spots on leaves and fruits, stunted growth, and damaged flowers or roots
• Plant viruses spread disease in two major modes:– Horizontal transmission, entering through
damaged cell walls – Vertical transmission, inheriting the virus from
a parent
Viroids and Prions: The Simplest Infectious Agents
• Viroids are circular RNA molecules that infect plants and disrupt their growth
• Prions are slow-acting, virtually indestructible infectious proteins that cause brain diseases in mammals
• Prions propagate by converting normal proteins into the prion version
• Normal prion protein are water soluble.– Prion’s not water soluble.– CJD and Mad cow Diseases
LE 18-13
Normalprotein
New prion
Prion Original prion
Many prions
Evolution
• Evolution of viruses– After first cells
• Fragments of cellular nucleic acids – Similar genomes to hosts oncoviruses
– Plasmids or Transposons• Selfreplicating genetic material in bacteria and fungi
What’s new?
• Prion’s can evolve: Scripps Research Institute in 2010…
• Each time the protein replicates they’re minor changes and errors. – Any changes in the environment
results in the best suited shapes multiplying faster.
What’s new?
• Prion’s found in Yeast and are a part of epigenetics
• MIT 2011– Yeast prions affect RNA
transcription that causes changes in the protein.
– Found in 255 of the 700 different species of yeast.
– May only be a yeast issue.
What’s new with viruses• 8% of our DNA sequence has viral genomes• 2000
– Syncytin a viral protein part of the evolution of placental mammals.
– This protein fuses cells together; required in development of the placenta and fetus
The Story of Syncytin grows• Chimps gorillas and primates all have the
same protein.– found syncytin 1 and 2 part of pre-eclampsia
• Dangerous high blood pressure if synctin 1 or 2 not working.
• Syncytin 2 slow’s mother’s immunes system down so it does not attack the fetus.
– 2005 found syncytin in mice, and it is required for survival of the fetus.
– Mouse and primate syncytin different sequences, different virus.
The Story of Syncytin grows• Rabbits have an additional different
syncytin sequence.• This sequence not in their closely related
cousins: the Pika.– Conclusion: new Syncytin infected rabbits
30mya.
The Story of Syncytin grows• Syncytin in
Carnivores
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