BIOS 242 Final Exam Study Guide & Practice Questions | Chamberlain

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BIOS242 / BIOS 242 Final Exam Study Guide BUNDLE

(Latest 2025): Fundamentals of Microbiology with Lab -

Chamberlain

why does average beak size increase in the population?

.....ANSWER.....birds with small beaks died and birds with large

beaks survived

the finch population involved, not its individual members




individual birds were subjected to natural selection and then

merely passed down heritable traits to their offspring ... or not

.....ANSWER.....the average beak size was affected (changes and

increased)

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what did the drought do to the proportion of small beak and

large beak alleles in this finch population? decreased small beak

alleles and increased large beak alleles

the forces of evolution




-evolution at its finest level is a change in allele frequencies in a

population over generations




- three main mechanisms cause allele frequency change:




- natural selection

- genetic drift

-gene flow

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other two not as concerned about:

- mutation can bring back a new allele

- non-random mating so like mated with like ; not focused on this

- only natural selection causes adaptive radiation

.....ANSWER.....only natural selection causes adaptation e

evolution does NOT equal mutation




- evolution can happen for other reasons than natural selection




-n there are many different factors that affect allele frequency

.....ANSWER.....

sources of genetic variation

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- mew genes and alleles can arise by mutation or gene

duplication




- sexual reproduction can add to the genetic variation among

individuals by recombining existing alleles at different places on

the genome ; mix and matching alleles via recombination of

chromosomes .....ANSWER.....-

1. formation of new alleles




- new alleles arise by mutation, a change in the nucleotide

sequence of DNA




- only mutations in cells that produce gametes can be passed to

offspring