Snowy Owl
Retired in 2010, In Memoriam
All thanks to AnneZ
Understanding Viruses
http://school.discovery.com/lessonpl...andingviruses/
Students will understand the following:
1. A virus is an infectious organism that reproduces within the cells of an infected host.
2. A virus is not alive until it enters the cells of a living plant or animal.
3. A virus contains genetic information wrapped in a protein coat.
4. Viruses can be useful as well as harmful.
5. A virus that mutates ensures its own survival by making itself unrecognizable to immune systems and vaccines.
6. Even viruses engineered for useful purposes can be harmful if unchecked.
Materials
For this lesson, you will need:
? Computer with Internet access
? Research materials on viruses
? Research materials on local weeds in your area
Procedures
1. Review with your students what they know about viruses. Be sure they understand that viruses occur in plants, as well as animals. (You might cite the tobacco mosaic virus, which kills tobacco plants.)
2. Tell your students that they are going to work on a project in which they will suggest a useful purpose for a virus, but first they need to know more about how viruses work.
3. Have students use print research materials and the Internet to add to their knowledge about viruses. (See Vocabulary and Links.) Students should understand the following before they continue with the activity:
1. A virus is an infectious organism that reproduces within the cells of an infected host.
2. A virus is not alive until it enters the cells of a living plant or animal.
3. A virus contains genetic information wrapped in a protein coat.
4. A virus that mutates ensures its own survival by making itself unrecognizable to immune systems and vaccines.
4. Divide your class into groups. Ask group members to imagine that they are part of a team of scientists assigned to stop a local weed epidemic by genetically engineering a virus that will target a local pest plant, or weed.
5. Discuss with the class how such a way of using a virus, while useful in some ways, could create dangers to the environment. Challenge students to suggest ways of safeguarding against such dangers.
6. Allow time for students to research the names and characteristics of local weeds, if necessary.
7. Instruct groups to perform the following tasks to complete their assignment:
1. Make a sketch of the target weed.
2. Make a sketch of how the virus will look.
3. Make a series of sketches showing the stages in the virus?s life cycle and the end result of its infection.
4. Describe safeguards you would take to keep the virus localized, make sure it isn?t harmful to animals or nontarget plants, and ensure that it doesn?t persist in the environment once the weeds are gone.
5. Make a display of your invention and post it in the classroom.
Adaptations
Have students work in groups to research viruses that have been used to control weed epidemics. Each group can write a report describing the outcome of such a program and the safeguards that were employed.
Discussion Questions
1. Explain the way in which a virus is able to reproduce and cause disease in a host.
2. Explain how World War I contributed to the flu pandemic of 1914. If there were no war, what probably would have happened to the flu strain? Give supporting statements to back your explanation.
3. Compare and contrast the work of Edward Jenner to that of Jonas Salk. How can the triumphs of these two virologists set an example for modern scientists researching new threats?
4. How might viruses help cure genetic diseases?
5. Describe two instances from the documentary in which disease was used as a weapon. How effective were the weapons? Is this practice still in use today? What are some of the potential consequences of using viruses in this manner?
6. How might the destruction of rain forests help spread new viral diseases?
Evaluation
You can evaluate your students on their projects using the following three-point rubric:
Three points: all sketches carefully executed and labeled; suggested safeguards reasonably realistic; safeguards clearly explained
Two points: sketches adequately executed and labeled; suggested safeguards reasonably realistic; explanation of safeguards lacks clarity
One point: sketches inadequate; suggested safeguards unrealistic; vague explanation of safeguards
You can ask your students to contribute to the assessment rubric by determining a minimum number of sketches for the display.
Extensions
Virus-Cell Comparison
Have each student draw and label a diagram of an animal cell and a virus, and then make a list of all the similarities and differences between the two. Students should then write a paragraph answering the following question: ?Why is a virus considered to exist between life and death??
Smallpox: To Be or Not to Be?
Smallpox disease was eliminated in 1979 after a worldwide effort to inoculate every man, woman, and child on Earth. Two collections of frozen smallpox virus have been preserved, one in Atlanta and the other in Moscow. Have students form discussion groups to talk about what they would do with the two collections. Students should list the pros and cons of keeping the smallpox virus in research laboratories, focusing on the ethics of eradicating life-forms that threaten the human population. Students can continue their study by researching how the CDC (Centers for Disease Control and Prevention) in Atlanta works to protect us from other viral invaders. They might also create fictional stories or plays exploring possible consequences that could result if smallpox should ever be reintroduced into society.
Suggested Readings
Viruses
Howard and Margery Facklam, Twenty-First Century Books, 1994
This highly readable narrative of the history of viruses and vaccines features color illustrations, enlargements of microscopic images, and black-and-white historical sketches.
"Viruses"
Peter Jaret, National Geographic, July 1994
Virus-related catastrophes and research triumphs are told in this illustrated article that examines viruses' vast capabilities.
Understanding Viruses
http://school.discovery.com/lessonpl...andingviruses/
Students will understand the following:
1. A virus is an infectious organism that reproduces within the cells of an infected host.
2. A virus is not alive until it enters the cells of a living plant or animal.
3. A virus contains genetic information wrapped in a protein coat.
4. Viruses can be useful as well as harmful.
5. A virus that mutates ensures its own survival by making itself unrecognizable to immune systems and vaccines.
6. Even viruses engineered for useful purposes can be harmful if unchecked.
Materials
For this lesson, you will need:
? Computer with Internet access
? Research materials on viruses
? Research materials on local weeds in your area
Procedures
1. Review with your students what they know about viruses. Be sure they understand that viruses occur in plants, as well as animals. (You might cite the tobacco mosaic virus, which kills tobacco plants.)
2. Tell your students that they are going to work on a project in which they will suggest a useful purpose for a virus, but first they need to know more about how viruses work.
3. Have students use print research materials and the Internet to add to their knowledge about viruses. (See Vocabulary and Links.) Students should understand the following before they continue with the activity:
1. A virus is an infectious organism that reproduces within the cells of an infected host.
2. A virus is not alive until it enters the cells of a living plant or animal.
3. A virus contains genetic information wrapped in a protein coat.
4. A virus that mutates ensures its own survival by making itself unrecognizable to immune systems and vaccines.
4. Divide your class into groups. Ask group members to imagine that they are part of a team of scientists assigned to stop a local weed epidemic by genetically engineering a virus that will target a local pest plant, or weed.
5. Discuss with the class how such a way of using a virus, while useful in some ways, could create dangers to the environment. Challenge students to suggest ways of safeguarding against such dangers.
6. Allow time for students to research the names and characteristics of local weeds, if necessary.
7. Instruct groups to perform the following tasks to complete their assignment:
1. Make a sketch of the target weed.
2. Make a sketch of how the virus will look.
3. Make a series of sketches showing the stages in the virus?s life cycle and the end result of its infection.
4. Describe safeguards you would take to keep the virus localized, make sure it isn?t harmful to animals or nontarget plants, and ensure that it doesn?t persist in the environment once the weeds are gone.
5. Make a display of your invention and post it in the classroom.
Adaptations
Have students work in groups to research viruses that have been used to control weed epidemics. Each group can write a report describing the outcome of such a program and the safeguards that were employed.
Discussion Questions
1. Explain the way in which a virus is able to reproduce and cause disease in a host.
2. Explain how World War I contributed to the flu pandemic of 1914. If there were no war, what probably would have happened to the flu strain? Give supporting statements to back your explanation.
3. Compare and contrast the work of Edward Jenner to that of Jonas Salk. How can the triumphs of these two virologists set an example for modern scientists researching new threats?
4. How might viruses help cure genetic diseases?
5. Describe two instances from the documentary in which disease was used as a weapon. How effective were the weapons? Is this practice still in use today? What are some of the potential consequences of using viruses in this manner?
6. How might the destruction of rain forests help spread new viral diseases?
Evaluation
You can evaluate your students on their projects using the following three-point rubric:
Three points: all sketches carefully executed and labeled; suggested safeguards reasonably realistic; safeguards clearly explained
Two points: sketches adequately executed and labeled; suggested safeguards reasonably realistic; explanation of safeguards lacks clarity
One point: sketches inadequate; suggested safeguards unrealistic; vague explanation of safeguards
You can ask your students to contribute to the assessment rubric by determining a minimum number of sketches for the display.
Extensions
Virus-Cell Comparison
Have each student draw and label a diagram of an animal cell and a virus, and then make a list of all the similarities and differences between the two. Students should then write a paragraph answering the following question: ?Why is a virus considered to exist between life and death??
Smallpox: To Be or Not to Be?
Smallpox disease was eliminated in 1979 after a worldwide effort to inoculate every man, woman, and child on Earth. Two collections of frozen smallpox virus have been preserved, one in Atlanta and the other in Moscow. Have students form discussion groups to talk about what they would do with the two collections. Students should list the pros and cons of keeping the smallpox virus in research laboratories, focusing on the ethics of eradicating life-forms that threaten the human population. Students can continue their study by researching how the CDC (Centers for Disease Control and Prevention) in Atlanta works to protect us from other viral invaders. They might also create fictional stories or plays exploring possible consequences that could result if smallpox should ever be reintroduced into society.
Suggested Readings
Viruses
Howard and Margery Facklam, Twenty-First Century Books, 1994
This highly readable narrative of the history of viruses and vaccines features color illustrations, enlargements of microscopic images, and black-and-white historical sketches.
"Viruses"
Peter Jaret, National Geographic, July 1994
Virus-related catastrophes and research triumphs are told in this illustrated article that examines viruses' vast capabilities.