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