Virus and Phage 2 Flashcards
Systemic effects of influenza results when infected cells release ___ proteins called ___ that activate the body’s defense system
Signaling
Cytokines
(T/F) Respiratory infection will result in the death of cells
True!
Influenza A virus is composed of ___RNA with (#) segments that contain (#) genes per segment
ssRNA
8
1-2
Influenza A virus contains ___ dependent RNA polymerase
RNA
(T/F) Influenza A is a non-envelope virus
False!
It’s an envelope virus
What role does HA play in the influenza A virus?
It is responsible for binding to the receptors on the host cell
(T/F) NA is essential for influenza A’s entry into a host cell
False!
It is not essential, but it does make entry easier
NA is an important ___ that is located on the surface ___ of influenza A
Antigen
Protein
Avian adapted flu binds what receptors?
Human adapted flu?
2-3 linked disaccharide receptors
2-6 linked disaccharide receptors
What kind of receptors are common and abundant in the cells that align the respiratory tract?
Alpha 2-6 linked disaccharide receptors
Why are swine good intermediate hosts for the flu?
They have both the 2-3 and 2-6 receptors
Describe the receptor-mediated endocytosis that is performed by the influenza virus
Acidification occurs inside the endosome of host
Decrease in pH leads to conformational change of HA protein
Virus genome sequence is released into the cytoplasm
How long can the flu live on:
- hard, nonporous (plastic)
- tissues, cloth, or paper
- hand
24 hours
15 minutes
5 minutes
What is the contagious period of the flu?
1 day before symptoms
5-7 days after symptoms
What is reassortment in reference to viruses?
It is when a single cell is infected with two types of a virus, allowing for mutation
