4.1 Viral Diseases Flashcards
Viruses are what?
Non living infectious agents
What mode of action do viruses take?
Invade cells and use cell machinery to replicate
Viruses are made of one protein and what else?
2 DNA or RNA
What is a virus in humans?
HIV
What is HIV?
Human immunodeficiency virus
Attacks immune system
(HIV) how is it spread?
Sex
Contaminated Needles
Mother to baby
(HIV) when do symptoms develop?
10 years after infection
(HIV) what is AIDS?
Advanced stage of HIV
acquired immunodeficiency syndrome
(HIV)what does HIV consist of?
Lipid bilayer
Glycoproteins
RNA
Reverse transcriptase in the capsid
(HIV) 1. via it’s glycoproteins HIV binds to what?
Receptors on the surface of T cells
(HIV)2. HIV fuses with the T helper cell membrane allowing RNA and enzymes to do what?
Enter cell
(HIV) 3. Reverse transcriptase does what?
Translates the RNA into DNA which moves into the nucleus and is incorporated into genetic material
(HIV) 4. mRNA is produced from the DNA and is used to do what?
Synthesis new viral proteins
(HIV)5. A new viral cell then does what?
Buds off from T helper cell
(HIV) 6. HIV replication results in what?
Death of T cells leading to weaker immune system
Give an example of a virus that can affect animals and humans:
Influenza
(Influenza) what does type A do?
Causes mild respiratory issues in humans and animals
(Influenza) how is it spread?
Birds shedding it in their saliva, mucous and faeces
(Influenza) responsible for large what?
Flu epidemics
What is a virus affecting plants?
Tobacco mosaic
(TMV) what plants does it affect?
Tobacco
Tomato
(TMV) what are the common symptoms:
Mosaic
Lead curling
Yellowing
(TMV) can only multiply in what?
Living cells
(TMV) what can it do in dead tissue?
Survive dormant
(TMV) can it be treated?
No plant needs to be discarded
(TMV) how is it spread?
Workers clothes and tools
