biochem 012 DNA and protein synthesis part 7 (watson crick griffith chargoff's rule translation
Home > Preview
The flashcards below were created by user
on FreezingBlue Flashcards.
how do viruses harm our cells?
- 1. viruses may damage or kill cells by causing the release of hydrolytic enzymes from lysosomes
- 2. some viruses cause infected cells to produce toxins that lead to disease symptoms
- 3. others have envelope proteins that are toxic
what are vaccines?
vaccines are harmless derivatives of pathogenic microbes that stimulate the immune system to mount defenses against the actual pathogen
true or false? antiviral drugs can help to treat, though not cure, viral infections
what is an emerging virus?
emerging viruses are those that appear suddenly or suddenly come to the attention of scientists
Give examples of recent emerging viruses
SARS, ebola, swine flu
true or false? outbreaks of "new" biral diseases in humans are usually caused by existing viruses that expand their host territory
how are flu epidemics caused?
flu epidemics are caused by new strains of influenza virus to which people have little immunity.
what is a pandemic?
a global epidemic
why are viral strains that jump species especially deadly?
they can exchange genetic information with other viruses to which humans have no immunity
what are prions?
prions are slow-acting, virtually indestructible infectious proteins that cause brain diseases in mammals
how do prions propagate?
they propagate by converting normal proteins into the prion version
give some examples of prion diseases
scrapie in sheep, mad cow disease, and Creutzfeldt-Jakob disease in humans
what types of cells does HIV attack and how does it enter these cells?
HIV attacks T helper cells. it enters these cells by using the CD4 molecule as the entrance point
what are the four ways in which viruses evade the immune system?
- 1. some lytic viruses wrap the cell's membrane around themselves
- 2. some force the expression of MHC I in the cell
- 3. Some lie dormant in the cell (lysogenic cycle)
- 4. some rapidly mutate and express different epitopes
MHC I is expressed in all cells except:
Red blood cells
what is interferon? what is its function?
interferon is a cytochine. It turns off neighboring cell replication machinery to keep the virus from reproducing.
how many strains of HPV are there?
what is the technical name of mad cow disease?
bovine spongiform encepalopathy
What would you like to do?
Home > Flashcards > Print Preview