Viruses (structure/taxonomy) Flashcards
A virus can consist of:
A. RNA or DNA and a capsid
B. RNA and DNA and a protein coat
C. proteins, cell membrane, and RNA
D. RNA or DNA and a cell membrane
E. RNA or DNA and an envelope
A
An influenza virus that has changed from an H1N1 to an H3N2 has undergone antigenic drift. True or false?
False
Viruses are:
A. Non living
B. Eukaryote
C. Prokaryote
D. Endospores
E. Acellular
E
Retroviruses are different because:
They can change their RNA to DNA
Viruses usually make their proteins on their ribosomes using the enzymes provided by the cell. True or false?
False
Most viruses are so small that they are filterable and can only be seen using an electron microscope. True or false?
True
What do all viruses have?
RNA or DNA, capsids, and nucleic acids
Viruses have ribosomes that are used to make their own proteins. True or false?`
False, viruses have no ribosomes
What is the difference between ss +RNA and ss -RNA?
+ RNA: can go straight to ribosome and act as mRNA
- RNA: first has to be copied (a positive complementary strand) and THEN goes to act as mRNA
What are the three shapes of viruses?
- Helical
- Polyhedral
- Complex
What is the most famous/common shape of viruses?
Icosahedral (from polyhedral)
What do capsids surround? What are they made of?
Nucleic acids; made of proteins (amino acid)
What are capsomeres?
The units that form a capsid
What are envelopes made of? Do all viruses have envelopes? Where are lipids found?
Made of bilayer of phospholipids (lipids)
No
Found in cell membranes
What are spikes?
The receptors of virus to bind to cell to infect
