Viruses And STIs

Question 1

what are viuses

Answer 1

a protein coat around a strand of genetic material

Question 2

what must viruses do to be able to reproduce to what specifically

Answer 2

• they must infect living cells

- specific types of viruses will only infect specific cells

Question 3

when does the life cycle of a virus start and what are the two ways it can reproduce

Answer 3

• it starts with when the virus infects a host cell
• many will reproduce with the lytic pathway
• but some may reproduce going in the lysogenic pathway first

Question 4

describe how viruses reproduce using the lytic pathway

Answer 4

• virus attaches itself to a specific host cell
• injects genetic material into cell
• virus uses proteins and enzymes in the host cell to replicate its genetic material
• producing new components for new viruses
• the viral components assemble, creating new viruses
• host cell breaks open which releases the virus to infect other cells

Question 5

describe how viruses reproduce using the lysogenic pathway

Answer 5

• injected genetic material incorporates itself into the genome of the cell
• viral genetic material gets replicated every time the host cell divides
• virus is dormant as no new viruses are made yet
• a trigger will eventually cause the viral genetic material to leave the genome of the host cell and enter the lytic pathway

Question 6

what are STIs

Answer 6

infections that are spread through sexual contact, including sexual intercourse

Question 7

what are the two STIs that we need to know about

Answer 7

• Chlamydia

- HIV

Question 8

what is chalmydia

Answer 8

a type of bacterium, but it acts in a similar way to a virus because it can only reproduce in a host cell

Question 9

what is the effect of chlamydia

Answer 9

although it doesnt show any immediate symptoms, it can result in infertility in men and women

Question 10

what are the three ways in which the spread of chlamydia can be reduced

Answer 10

• wearing a condom to prevent contact of sexual fluids
• screening so that it can be treated
• avoiding sexual contact

Question 11

what is HIV

Answer 11

it is the human immunodeficiency virus, which kills white bloods cells, which are very important for our immune responses

Question 12

what does a HIV infection usually lead to

Answer 12

the development of AIDS (acquired immune deficiency syndrome)

Question 13

what is AIDS

Answer 13

a condition where the immune system of someone deteriorates and eventually fails

Question 14

what is the effect of AIDS

Answer 14

as a result, the person becomes very vulnerable to opportunistic infections by other pathogens

Question 15

how is HIV spread

Answer 15

through infected bodily fluids such as blood or semen

Question 16

what are the 4 ways in which the spread of AIDS can be reduced

Answer 16

• wearing condoms during sex
• drug users avoiding using other peoples needles
• theres medication which reduces risk of AIDS being spread to another person
• screening to identify and treat the illness