Viruses

Video

Viruses

Unit 5 - Viruses and Bacteria (Ch. 18) 1.Identify the major components of a Bacterium and Viruses 2.List the two major stages / life cycles of Viruses 3.Define Vaccines 4.Identify the three types of groupings and shapes of bacteria 5.List at least 5 different types of bacteria and or viral infections that can affect the body

4: Same as a 3.0 but I can make inferences & application to the SWBAT’s 3: I COMPLETELY understand all parts of the SWBAT 2: I understand MOST of the SWBAT’s with teacher help 1:I understand a little of the SWBAT’s but need teacher help 0:I do NOT understand any part of the SWBAT’s and need help!

Have you ever had a vaccination? What is it? –A vaccine is a small injection of particles of virus that provide the human body with a defense against the disease

What is a Virus? A virus is a nucleic acid (DNA or RNA) in a protein coat It is NOT living – the only thing it does is replicate inside a host Host cell – the cell in which the viruses replicate Bacteriophage – a virus that infects a bacterium

Viral Structure Nucelic Acid: DNA or RNA –Contains information for copying Outer Protein Coat: Called a CAPSID Envelope: some viruses have this: it is made of the same materials as a cell membrane

How do Viruses Replicate? Viruses Replicate in 2 ways –It first must recognize and attach to a host cell’s membrane –One the virus gets inside – it will take over the cells operation

Virus Replication Lytic Cycle – Kills host instantly –The host cell is tricked into making virus copies –New viruses in the host cell build up, causing the host cell to burst! –New viruses move on to new host cells to re-infect and replicate Lysogenic Cycle – Allows some cells to live –Virus DNA is mixed with host cell DNA (Now it is called a provirus) –Host cell is not infected – it can carry on its own operation –Every time the host cell replicates, it replicates the provirus with it –At ANY time, the provirus can become activated and go into the Lytic cycle Can be caused by physical and or emotional stress

Common Viral Diseases Herpes Simplex I – cold sores, canker sores Herpes Simplex II – genital herpes Hepatitis A, B, and C Chicken Pox MeaslesMumpsRubellaSmallpoxPolioEbola The Flu HIV/AIDS

Unit 5 - Viruses and Bacteria (Ch. 18) 1.Identify the major components of a Bacterium and Viruses 2.List the two major stages / life cycles of Viruses 3.Define Vaccines 4.Identify the three types of groupings and shapes of bacteria 5.List at least 5 different types of bacteria and or viral infections that can affect the body

4: Same as a 3.0 but I can make inferences & application to the SWBAT’s 3: I COMPLETELY understand all parts of the SWBAT 2: I understand MOST of the SWBAT’s with teacher help 1:I understand a little of the SWBAT’s but need teacher help 0:I do NOT understand any part of the SWBAT’s and need help!