Pathogens which do not require contact between hosts are usually highly toxigeni
ID: 21803 • Letter: P
Question
Pathogens which do not require contact between hosts are usually highly toxigenic. They make their hosts terribly sick, becausea. dead hosts or hosts confined to their beds are not good agents for transmission.
b. the pathogen is spread by contaminated food or water.
c. pathogen mutation rates are higher in toxigenic hosts.
d. hosts recover more rapidly after they are buried.
e. a long bedridden period allows the pathogen time to mutate.
Natural selection acts on inherited variability, and this variability arises through
mutation. All mutations occur at a particular time, in one individual, at a
particular place in the genome; the initial frequency of the new mutant allele is
___. a. 0.001 b. 1/2N c. p d. ?/2N e. unknown
Mutations come in many variations such as single base changes and deletions.
One chromosomal mutation produces compound chromosomes in which arms
of the chromosomes are exchanged [ G---*---K and G---*---K becomes G---*---G
and K---*---K]. These types of arrangements are often seen as chromosomal
differences between species, but they ________________.
a. drastically reduce fitness while polymorphic. b. increase crossing over.
c. lower mutation rates in the compound chromosomes.
d. drastically increase fitness in the new species.
e. increase cancer rates.
Explanation / Answer
1) A 2) B 3) A