GCD 3022 EXAM 3 QUESTIONS AND
CORRECT ANSWERS
\.homologous recombination - ANSWERS-crossing over between eukaryotic
homologous chromosomes
\.What has Homologous recombination studied in?---------- because -------------- -
ANSWERS-fungal ascus. cells from meiosis are in order in the ascus and can not
change order
\.gene conversion - ANSWERS-one allele is converted to the allele on the
homologous chromosome
\.The Holliday Model - ANSWERS-Proposed originally by Robin Holliday; was
mostly correct except he thought it started by two single stranded DNA nicks
\.Double stranded breaks initiate the_____________________ that occurs in
meiosis. According to the ___________________ model - ANSWERS-homologous
recombination; Double strand Break Model
\.The double stranded Break Model - ANSWERS-
\.Double crossovers appear to be resolved ________________ - ANSWERS-one at
a time
,\.Causes of Gene Conversion - ANSWERS-DNA mismatch repair
DNA gap repair synthesis
\.site specific recombination - ANSWERS-requires very little sequence homology
between the recombining DNA molecules. Relatively short sequences; catalyzed
by specialized enzymes
\.site-specific recombination is used by - ANSWERS-1. Certain viruses when they
replicate their genomes
2. Certain viruses and transposons, to insert their DNA into host cell DNA
3. The mammalian immune system, to generate a diverse array of antibodies
\._______________ normally catalyzes site specific recombination between
________ sites during bacteriophage ______ replication - ANSWERS-Cre
recombinase
LoxP
P1
\.The Holliday Model for homologous recombination turned out to be correct,
except for one detail: The Holliday Model had homolgous recombination initiating
with _____________________ - ANSWERS-single stranded nicks
\.Following deliberate double stranded break, the break is enlarged into a
_______________. once crossovers are formed by_________________________
which leads to mismatched bases if the homologous chromosomes have DNA
, sequence differences. The mismatched bases are fixed using the
________________ - ANSWERS-single stranded nicks; gap; branch mitigation; DNA
mismatch repair
\.when certain __________ integrate their viral DNA into a bacterial chromosome
it creates a ________ - ANSWERS-bacteriophage;prophage
\.___________ or ________ are proteins produced by the immune system to
recognize foreign substances (______________) and to
______________________ - ANSWERS-Antibodies; immunoglobulins; antigens;
target them for destruction
\.Each type of antibody recognizes a single ____________ - ANSWERS-epitope
\.Each ______________ produces a single type of _______ which resides in the
____________ of the cell - ANSWERS-B cell; antibody; membrane
\.Each B cell produces _______ cells that turns onto ________________ which
secrete many copies of it's antibody into the blood stream - ANSWERS-daughter;
plasma cells
\.Antibodies are proteins produced by the immune system to recognize foreign
substances (viruses, bacteria, etc.) and to target them for destruction. The foreign
substances are also known as_______________. Each __________ (a type of
white blood cell) produces a single type of antibody which resides in the
membrane of the cell where it functions as a________________. - ANSWERS-
antigens; B cells; receptor
CORRECT ANSWERS
\.homologous recombination - ANSWERS-crossing over between eukaryotic
homologous chromosomes
\.What has Homologous recombination studied in?---------- because -------------- -
ANSWERS-fungal ascus. cells from meiosis are in order in the ascus and can not
change order
\.gene conversion - ANSWERS-one allele is converted to the allele on the
homologous chromosome
\.The Holliday Model - ANSWERS-Proposed originally by Robin Holliday; was
mostly correct except he thought it started by two single stranded DNA nicks
\.Double stranded breaks initiate the_____________________ that occurs in
meiosis. According to the ___________________ model - ANSWERS-homologous
recombination; Double strand Break Model
\.The double stranded Break Model - ANSWERS-
\.Double crossovers appear to be resolved ________________ - ANSWERS-one at
a time
,\.Causes of Gene Conversion - ANSWERS-DNA mismatch repair
DNA gap repair synthesis
\.site specific recombination - ANSWERS-requires very little sequence homology
between the recombining DNA molecules. Relatively short sequences; catalyzed
by specialized enzymes
\.site-specific recombination is used by - ANSWERS-1. Certain viruses when they
replicate their genomes
2. Certain viruses and transposons, to insert their DNA into host cell DNA
3. The mammalian immune system, to generate a diverse array of antibodies
\._______________ normally catalyzes site specific recombination between
________ sites during bacteriophage ______ replication - ANSWERS-Cre
recombinase
LoxP
P1
\.The Holliday Model for homologous recombination turned out to be correct,
except for one detail: The Holliday Model had homolgous recombination initiating
with _____________________ - ANSWERS-single stranded nicks
\.Following deliberate double stranded break, the break is enlarged into a
_______________. once crossovers are formed by_________________________
which leads to mismatched bases if the homologous chromosomes have DNA
, sequence differences. The mismatched bases are fixed using the
________________ - ANSWERS-single stranded nicks; gap; branch mitigation; DNA
mismatch repair
\.when certain __________ integrate their viral DNA into a bacterial chromosome
it creates a ________ - ANSWERS-bacteriophage;prophage
\.___________ or ________ are proteins produced by the immune system to
recognize foreign substances (______________) and to
______________________ - ANSWERS-Antibodies; immunoglobulins; antigens;
target them for destruction
\.Each type of antibody recognizes a single ____________ - ANSWERS-epitope
\.Each ______________ produces a single type of _______ which resides in the
____________ of the cell - ANSWERS-B cell; antibody; membrane
\.Each B cell produces _______ cells that turns onto ________________ which
secrete many copies of it's antibody into the blood stream - ANSWERS-daughter;
plasma cells
\.Antibodies are proteins produced by the immune system to recognize foreign
substances (viruses, bacteria, etc.) and to target them for destruction. The foreign
substances are also known as_______________. Each __________ (a type of
white blood cell) produces a single type of antibody which resides in the
membrane of the cell where it functions as a________________. - ANSWERS-
antigens; B cells; receptor
