Question

What exactly is immunity to disease, and why does it eventually weaken.

Answer 1

A population of organisms with natural immunity at the outbreak of a disease or illness is still likely to be affected by the disease over time for all of the reasons listed here, EXCEPT

the population can lose its immunity through births

the population can have contagious individuals move into its area and become infected

the population is highly susceptible to suffering environmental mutation when a disease arises

most populations experience waning immunity to the disease over time

Answer 2

Here is my guess,
I think that a population can lose its immunity through births, as human babies have to get a vaccine even if their parents got one.
If they are exposed to the disease, I do not believe that the disease can make them sick because they have immunity and the contagious individual cannot do anything to weaken it.
This one, I do not believe is true. Outbreak would not happen because natural selection would kill of the individuals with the mutation before they reproduce.
This one is probably true, although I am not sure why.

The funny thing is, the only way I heard that a disease can infect a immune population is if it acquires a mutation that aids it infect.

Answer 3

I am guessing that the answer choice is the third, as it seems the most simple and basic. A population that is immune will accuire mutations, but the individuals with the mutation would not e able to survive long enough for them to reproduce.

Answer 4

Oml, has no one taken biology? We become immune because our body is able to find the virus and kill it, with age, and surgery (other things) weakens it naturally. Also, the virus can mutate and change causing out body not to recognize the virus cell and kill it off. so, C

Answer 5

Thanks!

Answer 6

Thanks!

Answer 7

No problem