CO: I will compare and describe the structure of a virus to a cell.LO: I will read and watch a video about viruses. I will build a virus.
Science Fact of the Day: Some migratory birds have a "magnetic compass" in their body (a sense called Magnetoreception) to help them navigate using Earth's magnetic field.
Anticipation Guide: Discuss the following statements with a partner. Determine if you think they are true or false. • Viruses affect us just like bacteria. • Viruses have DNA. • Viruses can be cured by antibiotics. • Viruses are not alive. • Being a zombie is caused by a virus.
Generalized Structure of Viruses Viral components • Nucleic acids • DNA or RNA • Capsid • Protein • Envelope
Viruses are highly specific to the cells they infect Examples: 1) plant viruses infect plant cells 2) animal viruses infect only certain related species of animals 3) bacterial viruses (bacteriophage) infect only certain types of bacteria. So, what about zombies?
Think-Pair-Share Are viruses alive? (Justify your answer)
Viruses have both living and nonliving characteristics. Living characteristics of viruses: • They reproduce at a fantastic rate, but only in living host cells. • They can mutate. • They contain DNA or RNA
Nonliving characteristics of viruses: • They are acellular, they contain no cytoplasm or cellular organelles. They are not made of cells. • They carry out no metabolism on their own and must replicate using the host cell's metabolic machinery. • They do not grow or develop
Viruses are NOT alive because they DO NOT have ALL of the characteristics of life.
Viruses range in size from 20 nanometers (nm) – 250 nanometers (nm) 1 nm = 0.00000004 inches If a cell was the size of your classroom, then an average virus would be the size of a softball. proteins animal cells atom bacteria viruses 0 m 10-5 m 10-6 m 10-7 m 10-8 m 10-9 m Go five more feet! 10-10 m A virus’ size helps it to reproduce. We’ll talk about this tomorrow.
Virus Structure Cell Structure
Virus Structure Activity • Create a model of a virus as instructed by your teacher • Label the model correctly • Summarize in 14 words how the structure of your virus is different than a cell.