Vocabulary: bacteriophage, capsid, host cell, lyse, lytic cycle, virus
Prior Knowledge Questions (Do these BEFORE using the Gizmo.)
A computer virus is a program that can copy itself and infect a computer without the permission of the owner. How do you think a computer virus compares to a real virus?
Have you ever been infected with a virus, such as the cold virus or flu virus?
If so, how did the virus affect you?
A virus is a microscopic particle that can infect a cell. Viruses are primarily composed of a protein coat, called a capsid, and nucleic acid. In the Virus Lytic Cycle Gizmo™, you will learn how a virus infects a cell and uses the cell to produce more viruses.
Viruses are extremely small. A typical virus is about 100 times smaller than a single cell, such as a bacterium. Label the virus and a bacterial cell in the image at right.
Bacteriophages are viruses that infect bacteria. Based on the diagram at left, label the head, tail, tail fibers, and the strand of nucleic acid in the image at right.
Get the Gizmo ready:
If necessary, click Reset ().
Introduction: Unlike living organisms, viruses cannot reproduce on their own. Instead, viruses infect host cells, taking over the cell’s machinery to produce more viruses. This process is called the lytic cycle.
Question: What are the steps of the lytic cycle?
Observe: Use the navigation arrows on the DESCRIPTION tab to read about the stages of the lytic cycle. Using your own words, summarize each step of the cycle.
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Activity A (continued from previous page)