Viruses

Question 1

What is a virus?

Answer 1

A strand of genetic material (RNA or DNA) in a protein coat called capsid

Question 2

In your opinion is it living or non-living?

Answer 2

Non-living:
-doesn’t take in nutrition
-doesn’t eliminate waste
-can only reproduce in a specific host

Question 3

Define parasitic bacteria

Answer 3

They can only survive within a host

Question 4

R nought or R0

Answer 4

The reproductive number R defines the average number of individuals that a person infected with a particular pathogen infects

Question 5

Transmission

Answer 5

How a virus moves from one organism to another (Rabies is through blood contact, Covid19 is through air -borne droplets)

Question 6

Vector

Answer 6

Animal that moves the virus into another species (Mosquito are a vector of malaria)

Question 7

Fomite

Answer 7

An inanimate object that’s contained which can transfer the disease to a new host
(computer keyboard can transfer to other people)

Question 8

Epidemic

Answer 8

A disease that has spread across a population or region

Question 9

Pandemic

Answer 9

A disease that has spread across multiple country or continent

Question 10

What are 2 cycles virus go through?

Answer 10

Lytic cycle and lysogenic cycle

Question 11

What are the 2 difference between the cycle

Answer 11

Lytic cycle: very fast reproduction, happens rapidly
Lysogenic cycle: the virus hides in the DNA for a long time and continues to make copies of itself, then when a trigger happens the virus starts it’s effects

Question 12

What is a prion?

Answer 12

A prion is a protein that is not folded correctly, it affects the shape of proteins it contacts

Question 13

What is parasitic bacteria?

Answer 13

It can ONLY survive inside a specific host, where as a virus can survive outside a host such as a counter top.

Question 14

State steps of lytic cycle

Answer 14

1. Attachment: The bateriophage is attached to the surface of host
2. Entry: Viral DNA enters the host
3. Replication: Viral DNA parts are copied by ribosomes in the host
4. Assembly: Viral parts come together and make into a virus
5. Lysis and release: Cell wall of host breaks and host cell dies, releasing newly made phages

Question 15

State steps of lysogenic cycle

Answer 15

1. Attachment and entry: Nuclei acid enters the host
2. Provirus formation: The provirus hides in the DNA of host cell
3. Cell division -binary fission: creates new cells with the provirus in the DNA
4. Lytic cycle (trigger): a trigger happens causing the provirus to release from the chromosome
5. Assembly: Viral parts are made and copied
6. Lysis and release:Cell wall of host breaks and host cell dies, releasing newly made phages