Ch. 20 Viruses Flashcards
(19 cards)
What is a virus?
a nonliving particle made of proteins, nucleic acids, and sometimes lipids
Describe the basic structure of a virus
made of proteins, nucleic acids such as DNA or RNA, and sometimes, lipids
What surrounds all viruses? What is it made of?
Capsid-Protein coat that surrounds a virus
What does a virus have inside that has the instructions for making copies of the virus?
RNA or DNA but never both
TRUE OR FALSE
Viruses only come in 3 shapes, 3 sizes, and 2 structures
FALSE many shapes, many sizes and many structures
What is on the outside of a virus that acts as identifiers?
proteins
What do specific proteins on the outside of a virus do? Why do they do this?
Act as identifiers, these protein identifiers recognize proteins and bind to specific protein receptors on a cell
Most viruses infect a ____________ of cell.
specific type
What are viruses that only infect bacteria called?
bacteriophages
Why are viruses not living?
Because they cannot reproduce on their own
What are the two types of viral infections?
Lytic & Lysogenic
What does it mean to lyse the cell?
The cell bursts open releasing the virus particles
Burst open the cell membrane
Which of the two viruses automatically begins chopping up the host cell’s DNA?
Lytic
Which viral infection never leaves your body? Why?
-Lysogenic because it incorporates the viral DNA into the HOST DNA
-because the cell copies its own DNA and the viral material for generations and lives in union
What is a prophage?
Viral DNA that is incorporated into the Host DNA
What are the two ways that viruses cause diseases?
The virus directly destroys the host
The virus affects cellular processes that upset homeostasis
What are two ways we can prevent viruses?
Receive Vaccinations-injection of a weakened, or a similar but less dangerous, pathogen to produce immunity. Vaccination is an injection of a vaccine
Practicing Personal hygiene- washing hands, taking showers, not sharing certain. Keep fingers off face and mouth because fingers touch so many things so we would be preventing ingesting the virus
What treatments do we have for viruses? Explain what is used and what they do
-Use of antiviral drugs, they attack specific viral enzymes that the host cell does not have. They help give speed recovery or stop activation
-Tamiflu works by blocking the enzyme that flu viruses need to multiply and help diminish severity of flu symptoms
What does a virus have to have to survive? Why?
Has to have living host. They cannot reproduce on their own and solely rely on the host´s cellular mechanisms.
