PCB 3044 Exam 2 Questions With Correct
Answers
genotype |- |CORRECT |ANSWER✔✔-the |genetic |makeup |of |an |individual
evolution |- |CORRECT |ANSWER✔✔-change |in |allele |frequencies |in |a |population |over |time
descent |with |modification |- |CORRECT |ANSWER✔✔-passing |traits |from |parent |to |offspring
As |a |population |accumulates |differences |over |time |and |a |new |species |forms, |it |is |different |
from |its |ancestors |- |CORRECT |ANSWER✔✔-But |the |new |species |shares |many |of |the |same |
characteristics |as |its |ancestors |and |resembles |them
natural |selection |- |CORRECT |ANSWER✔✔-Individuals |with |certain |heritable |traits |survive |and |
reproduce |more |successfully |than |other |individuals.
Individuals |with |__________ |traits |have |more |offspring, |and |their |alleles |will |___________ |in |
frequency |in |the |population. |- |CORRECT |ANSWER✔✔-favored; |increase
phenotype |- |CORRECT |ANSWER✔✔-observable |characteristics |that |are |determined |by |the |
genotype
mutation |- |CORRECT |ANSWER✔✔-a |change |in |DNA |of |a |gene. |Mutation |provides |the |raw |
material |on |which |evolution |is |based
Recombination |- |CORRECT |ANSWER✔✔-the |rearrangement |of |genetic |material, |especially |by |
crossing |over |in |chromosomes |or |by |the |artificial |joining |of |segments |of |DNA |from |different |
,organisms. |also |produce |different |genotypes |within |a |population. |recombination |rearranges |
the |raw |material |into |new |combinations.
types |of |natural |selection |- |CORRECT |ANSWER✔✔-directional |selection, |stabilizing |selection |
and |disruptive |selection
directional |selection |- |CORRECT |ANSWER✔✔-individuals |at |one |phenotypic |extreme |are |
favored |Ex. |Drought |favored |large |beak |size |in |medium |ground |finches
stabilizing |selection |- |CORRECT |ANSWER✔✔-individuals |with |an |intermediate |phenotype |are |
favored |Ex. |Parasitic |wasps |of |Eurosta |fly |select |for |larvae |in |small |gall |size; |while |birds |select |
for |Eurosta |larvae |in |large |gall
disruptive |selection |- |CORRECT |ANSWER✔✔-individuals |at |both |phenotypic |extremes |are |
favored |Ex. |African |seedcrackers |(birds) |have |two |food |sources
genetic |drift |- |CORRECT |ANSWER✔✔-occurs |when |chance |events |determine |which |alleles |are |
passed |to |the |next |generation. |it |is |significant |only |for |small |populations
genetic |drift |has |four |effects |on |evolution |in |small |populations |- |CORRECT |ANSWER✔✔-1. |It |
acts |by |chance |alone, |thus |causing |allele |frequencies |to |fluctuate |at |random. |Some |alleles |
may |disappear, |others |may |reach |100% |frequency |(fixation). |
2. |Because |some |alleles |are |lost, |genetic |variation |of |the |population |is |reduced.
3. |Frequency |of |harmful |alleles |can |increase |if |the |alleles |have |only |mildly |deleterious |effects.
4. |Differences |between |populations |can |increase. |Chance |events |may |lead |to |allele |fixation |in |
one |population |and |loss |from |another |population.
gene |flow |- |CORRECT |ANSWER✔✔-alleles |move |between |populations |via |movement |of |
individuals |or |gametes
, gene |flow |has |two |effects |- |CORRECT |ANSWER✔✔-1. |populations |become |more |similar |
genetically
2. |new |alleles |can |be |introduced |into |a |population
Natural |selection |is |the |only |evolutionary |mechanism |that |consistently |causes |_____________ |
_________ |- |CORRECT |ANSWER✔✔-adaptive |evolution
adaptations |- |CORRECT |ANSWER✔✔-improve |the |ability |to |survive |and |reproduce. |This |
include |morphological |and |physiological |features
adaptive |evolution |- |CORRECT |ANSWER✔✔-process |by |which |traits |that |confer |advantages |in |
survival |or |reproduction |tend |to |increase |in |frequency |over |time
Examples |of |rapid |adaptive |evolution: |- |CORRECT |ANSWER✔✔-1. |Antibiotic |resistance |in |
bacteria
2. |insecticide |resistance |in |insects
clines |- |CORRECT |ANSWER✔✔-patterns |of |change |in |a |characteritic |over |a |geographic |region
phenotypic |plasticity |- |CORRECT |ANSWER✔✔-One |genotype |may |produce |different |
phenotypes |under |different |environmental |conditions.
Lack |of |genetic |variation |- |CORRECT |ANSWER✔✔-If |there |is |no |beneficial |allele, |adaptive |
evolution |at |that |gene |cannot |occur |Ex. |Initially, |mosquito |populations |lacked |alleles |for |
pesticide |resistance |so |the |pesticides |were |effective. |Advantageous |alleles |arise |by |chance.
Evolutionary |history |- |CORRECT |ANSWER✔✔-Natural |selection |works |on/modifies |traits |that |
already |exist. |Organisms |have |certain |characteristics |and |lack |others |because |of |their |ancestry.
|EX: |Dolphins |evolved |from |terrestrial |mammals; |they |have |lungs |and |cannot |"breathe" |
underwater.
Answers
genotype |- |CORRECT |ANSWER✔✔-the |genetic |makeup |of |an |individual
evolution |- |CORRECT |ANSWER✔✔-change |in |allele |frequencies |in |a |population |over |time
descent |with |modification |- |CORRECT |ANSWER✔✔-passing |traits |from |parent |to |offspring
As |a |population |accumulates |differences |over |time |and |a |new |species |forms, |it |is |different |
from |its |ancestors |- |CORRECT |ANSWER✔✔-But |the |new |species |shares |many |of |the |same |
characteristics |as |its |ancestors |and |resembles |them
natural |selection |- |CORRECT |ANSWER✔✔-Individuals |with |certain |heritable |traits |survive |and |
reproduce |more |successfully |than |other |individuals.
Individuals |with |__________ |traits |have |more |offspring, |and |their |alleles |will |___________ |in |
frequency |in |the |population. |- |CORRECT |ANSWER✔✔-favored; |increase
phenotype |- |CORRECT |ANSWER✔✔-observable |characteristics |that |are |determined |by |the |
genotype
mutation |- |CORRECT |ANSWER✔✔-a |change |in |DNA |of |a |gene. |Mutation |provides |the |raw |
material |on |which |evolution |is |based
Recombination |- |CORRECT |ANSWER✔✔-the |rearrangement |of |genetic |material, |especially |by |
crossing |over |in |chromosomes |or |by |the |artificial |joining |of |segments |of |DNA |from |different |
,organisms. |also |produce |different |genotypes |within |a |population. |recombination |rearranges |
the |raw |material |into |new |combinations.
types |of |natural |selection |- |CORRECT |ANSWER✔✔-directional |selection, |stabilizing |selection |
and |disruptive |selection
directional |selection |- |CORRECT |ANSWER✔✔-individuals |at |one |phenotypic |extreme |are |
favored |Ex. |Drought |favored |large |beak |size |in |medium |ground |finches
stabilizing |selection |- |CORRECT |ANSWER✔✔-individuals |with |an |intermediate |phenotype |are |
favored |Ex. |Parasitic |wasps |of |Eurosta |fly |select |for |larvae |in |small |gall |size; |while |birds |select |
for |Eurosta |larvae |in |large |gall
disruptive |selection |- |CORRECT |ANSWER✔✔-individuals |at |both |phenotypic |extremes |are |
favored |Ex. |African |seedcrackers |(birds) |have |two |food |sources
genetic |drift |- |CORRECT |ANSWER✔✔-occurs |when |chance |events |determine |which |alleles |are |
passed |to |the |next |generation. |it |is |significant |only |for |small |populations
genetic |drift |has |four |effects |on |evolution |in |small |populations |- |CORRECT |ANSWER✔✔-1. |It |
acts |by |chance |alone, |thus |causing |allele |frequencies |to |fluctuate |at |random. |Some |alleles |
may |disappear, |others |may |reach |100% |frequency |(fixation). |
2. |Because |some |alleles |are |lost, |genetic |variation |of |the |population |is |reduced.
3. |Frequency |of |harmful |alleles |can |increase |if |the |alleles |have |only |mildly |deleterious |effects.
4. |Differences |between |populations |can |increase. |Chance |events |may |lead |to |allele |fixation |in |
one |population |and |loss |from |another |population.
gene |flow |- |CORRECT |ANSWER✔✔-alleles |move |between |populations |via |movement |of |
individuals |or |gametes
, gene |flow |has |two |effects |- |CORRECT |ANSWER✔✔-1. |populations |become |more |similar |
genetically
2. |new |alleles |can |be |introduced |into |a |population
Natural |selection |is |the |only |evolutionary |mechanism |that |consistently |causes |_____________ |
_________ |- |CORRECT |ANSWER✔✔-adaptive |evolution
adaptations |- |CORRECT |ANSWER✔✔-improve |the |ability |to |survive |and |reproduce. |This |
include |morphological |and |physiological |features
adaptive |evolution |- |CORRECT |ANSWER✔✔-process |by |which |traits |that |confer |advantages |in |
survival |or |reproduction |tend |to |increase |in |frequency |over |time
Examples |of |rapid |adaptive |evolution: |- |CORRECT |ANSWER✔✔-1. |Antibiotic |resistance |in |
bacteria
2. |insecticide |resistance |in |insects
clines |- |CORRECT |ANSWER✔✔-patterns |of |change |in |a |characteritic |over |a |geographic |region
phenotypic |plasticity |- |CORRECT |ANSWER✔✔-One |genotype |may |produce |different |
phenotypes |under |different |environmental |conditions.
Lack |of |genetic |variation |- |CORRECT |ANSWER✔✔-If |there |is |no |beneficial |allele, |adaptive |
evolution |at |that |gene |cannot |occur |Ex. |Initially, |mosquito |populations |lacked |alleles |for |
pesticide |resistance |so |the |pesticides |were |effective. |Advantageous |alleles |arise |by |chance.
Evolutionary |history |- |CORRECT |ANSWER✔✔-Natural |selection |works |on/modifies |traits |that |
already |exist. |Organisms |have |certain |characteristics |and |lack |others |because |of |their |ancestry.
|EX: |Dolphins |evolved |from |terrestrial |mammals; |they |have |lungs |and |cannot |"breathe" |
underwater.
