Presentation on theme: "THE MICROSCOPE 7 th Grade Lab Activity. Do Now… ◦ Which of the scientists who contributed to the development of the cell theory do you think is the most."— Presentation transcript:
Do Now… ◦ Which of the scientists who contributed to the development of the cell theory do you think is the most important? Explain your thoughts.
Objectives ◦ Students will… ◦ Learn the names of microscope parts ◦ Learn how to use a microscope ◦ Prepare objects for viewing under a microscope ◦ Examine several objects under a microscope ◦ Determine how the lens system of a microscope changes the position of an object being viewed
The Microscope ◦ A microscope is a scientific tool used to see very small objects. ◦ Objects you cannot see with your eyes alone can be seen using a microscope. ◦ In this experiment you will look at a small letter e cut from a magazine, some thread and a strand of hair. ◦ Activity will be completed in partners ◦ Please read through the lab carefully and follow all directions. ◦ Review how to prepare a slide.
Partner Pairs ◦ Anna/Gabby ◦ Maddie/Caroline H. ◦ Megan/Julia ◦ Caroline K./Rachel ◦ Abby/Gabrielle ◦ Salvo/Owen ◦ Ryan/Jake ◦ Greyson/Michael S. ◦ Michael C./Sean
For Next Time…. ◦ Read pgs. 232-235. ◦ Finish lab if needed.
Do Now… ◦ Define bacteria, virus and host cell on index cards.
Objectives Students will… ◦ Explain how a virus makes copies of itself ◦ Identify the benefits of viruses ◦ Investigate some uses of viruses
What are viruses? ◦ A virus is a strand of hereditary material surrounded by a protein coating. ◦ They don’t have a nucleus, other organelles or a cell membrane. ◦ A virus multiples itself by making copies with help of a living cell a called a host cell.
Active Viruses pg. 232 The virus attaches to a specific host cell. The virus’s hereditary material enters the host cell. The virus’s HM cause the cell to make viral HM and proteins. New viruses form inside the host cell. New viruses are released as the host cell bursts open and is destroyed.
Inactive Viruses ◦ Some viruses can be inactive and are called latent. ◦ Latent means that after the virus enters the host cell, its hereditary material becomes part of a host cell’s hereditary material. ◦ It does not immediately cause the host cell to make new viruses or destroy it. ◦ Ex: Cold sores-virus stays in people forever but only causes symptoms once and a while.
How do viruses affect organisms? ◦ Viruses affect many living things. ◦ Most viruses only affect specific kinds of cells---limited to only one host species. ◦ This is why humans can have viruses that don’t affect other animals or plants and vice versa. ◦ A few viruses affect a broad range of hosts like the rabies virus. ◦ A virus cannot move by itself, but can reach a host’s body in several ways. ◦ 1) Carried by wind ◦ 2) Inhaled by animal ◦ Finally, viruses and the attachment sites of the host cell must match exactly, like a puzzle.
Treating and Preventing Viral Diseases Viral Diseases can be prevented by Vaccinating people Separating patients who have viral diseases Controlling pests that spread disease Vaccinating pets and farm animals Improving sanitary conditions
Research with Viruses ◦ Gene therapy/transfer is one way that viruses are helpful. ◦ 1) Normal hereditary material is enclosed in viruses. ◦ 2) The viruses infect the defective cells ◦ 3) New hereditary materials enter the cells and replace the defective hereditary material.
Research with viruses ◦ An active area of viral research is HIV/AIDS research. ◦ HIV= Human immune-deficiency virus, a virus that attacks the immune system. ◦ AIDS=Acquired Immune Deficiency Syndrome. ◦ A weak immune system means the body cannot fight other diseases or infections like pneumonia and certain types of cancer. ◦ Currently, there is no known cure for AIDS.
Videos ◦ Introduction to Viruses Introduction to Viruses ◦ Viruses Viruses
For Next Time… ◦ Complete Virus Worksheet (Reinforcement)