microbes and fungi Flashcards
a biological particle made of nucleic acid surrounded by a protein capsid
virus
the protein coat of a virus
capsid
a virus that infects bacteria
bacteriophage
How are viruses similar to cells?
- made of some of the same chemicals 2. can reproduce (but need a host cell) 3. can evolve over time
How are viruses different from cells?
- no cell parts 2. no metabolism - don’t need energy 3. no growth or development 4. no response to environment 5. must have a host cell to reproduce
Which evolved first, viruses or bacteria? How do you know?
bacteria - because viruses couldn’t have reproduced without a host cell
Describe a lytic infection.
The virus takes over the cell right away, forces the cell to make more viruses, and then splits open the cell allowing the virus to spread to more cells.
Describe a lysogenic infection.
The virus quietly injects DNA into the cell. The virus prophage is copied every time the cell reproduces. Then some environmental trigger causes the cell to become lytic.
the splitting open of a cell
lysis
viral DNA that has been inserted into host DNA
prophage
a virus that uses RNA as its genetic code
retrovirus
a dead or weakened germ that helps prepare the immune system to fight off the virus
vaccine
Who developed the first vaccine and from what?
Edward Jenner - cowpox virus protected from smallpox
Why don’t antibiotics work on viruses?
viruses aren’t living - can’t kill something that isn’t alive
Other than proteins and nucleic acids, what chemical were viruses made up of?
lipids
What is the purpose of the proteins in the viral capsid?
bind the virus to its host
What contains the instructions for making new copies of a virus?
coded for in the viral DNA or RNA
Give 3 examples of viral diseases.
AIDS/HIV, measles, polio, smallpox, ebola, herpes, cold, influenza, chicken pox, hepatitis, West Nile, HPV
How do viruses cause diseases?
destroy cells and affect cell processes
cells without a nucleus and without membrane-bound cell organelles like mitochondria or chloroplasts
prokaryotes
What are the only cells that are prokaryotes?
bacteria
Name and describe the two major groups of bacteria.
- Archaea - bacteria with genes and metabolic activities more similar to eukaryotes, no peptidoglycan in cell walls 2. Eubacteria - common bacteria with peptidoglycan cell walls
long, whip-like structure used by bacteria to move
flagella
short hair-like structures used by bacteria to anchor to other surfaces
pili (pilus)













