Transcript Virus - LACOE
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_3 161_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/mnpag es/dispages/ebola.htm
• http://www.biology.arizona.edu/cell_bio/tut orials/pev/page4.html
• 82-84; 121-129; 153-157; 174-178; 185-192; 204-206; 323-325
Science @ Home
• Email me tonight your answers [email protected]
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
• Capsids – Protein coats – Phages
Structure
Structure
• 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
LE 18-4c
Membranous envelope Capsid RNA Glycoprotein 80 –200 nm (diameter) 50 nm Influenza viruses
• 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
Head Tail sheath Tail fiber 80
225 nm DNA 50 nm Bacteriophage T4
LE 18-5
Entry into cell and uncoating of DNA DNA Capsid VIRUS Replication HOST CELL Viral DNA Transcription Viral DNA mRNA Capsid proteins Self-assembly of new virus particles and their exit from cell
Reproduction
Class/Family Envelope Examples/Disease
I. Double-stranded DNA (dsDNA)
Adenovirus No Papovavirus No Herpesvirus Yes Poxvirus Yes Respiratory diseases, animal tumors Papillomavirus (warts, cervical cancer): polyomavirus (animal tumors) Herpes simplex I and II (cold sores, genital sores); varicella zoster (shingles, chicken pox); Epstein-Barr virus (mononucleosis, Burkitt ’ s lymphoma) 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 Coronavirus Flavivirus Togavirus No Yes Yes Yes Rhinovirus (common cold); poliovirus, hepatitis A virus, and other enteric (intestinal) viruses Severe acute respiratory syndrome (SARS) Yellow fever virus, West Nile virus, hepatitis C virus 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
Glycoprotein Reverse transcriptase Viral envelope Capsid RNA (two identical strands)
• 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
HIV Membrane of white blood cell 0.25 µm HIV entering a cell Viral RNA RNA-DNA hybrid DNA HOST CELL Reverse transcription RNA genome for the next viral generation Chromosomal DNA NUCLEUS Provirus mRNA New HIV leaving a 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
Prion Normal protein Original prion New 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