Virus Structure

Bellwork

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.

Viruses

Anticipation Guide: Discuss the following statements with a partner. Determine if you

think they are true or false.

1. Viruses affect us just like bacteria.2. Viruses have DNA.3. Viruses can be cured by antibiotics.4. Viruses are not alive.5. Being a zombie is caused by a virus.

OVERVIEW

Generalized Structure of Viruses

Viral components–Nucleic acids• DNA or RNA

–Capsid• Protein

– Envelope8

Generalized Structure of Viruses

Generalized Structure of Viruses

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Viruses are highly specific to the cells they infect

Examples: 1) plant viruses infect plant cells2) animal viruses infect only certain related species of animals3) 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.

If a cell was the size of your classroom, then an average virus would be the size of a softball.

Viruses range in size from 20 nanometers (nm) – 250 nanometers (nm)

1 nm = 0.00000004 inches

10-5 m10-6 m

10-7 m

10-8 m

10-9 m

10-10 m

0 m

virusesanimal

cellsbacteriaprot

eins

atom

Go five more feet!

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.