BIMM 120 Final questions well
answered graded A+
genome - correct answer ✔✔ genetic information that defines an organism
what do microbial genomes consist of? - correct answer ✔✔ one or more DNA chromosomes
that are usually circular, some linear.
plus plasmids that are usually circular but can be linear
vertical transmission - correct answer ✔✔ from parent to child gene transfer
horizontal transmission - correct answer ✔✔ transfer of pieces of DNA from one cell to another
structural gene - correct answer ✔✔ produces a functional RNA ("coding DNA").
-mRNA which encodes a protein
-rRNA, tRNA, small noncodingRNA
DNA control sequence - correct answer ✔✔ REGULATES THE EXPRESSION OF A STRUCTURAL
GENE
-DOES NOT ENCODE AN RNA
what is e.coli's genome size? - correct answer ✔✔ 4,600 kb(4 million base pairs) pair
chromosome, no plasmid though. humans have 3 billion kb for comparison
range of genome size in bacteria and archea chromosomes? - correct answer ✔✔ 460- >9000 kb
,operon - correct answer ✔✔ unit that contains genes with related functions that need to be
expressed together. has like 3 genes with one promotor that makes three proteins
(polycistronic)
regulon - correct answer ✔✔ different genes or operons controlled by the same transcription
factor. regulates synthesis of sigma factor that directs expression of all the genes
regulation of genes - correct answer ✔✔ control protein (transcription factor) will bind to
different places in the genome to coordinate transcription
positive supercoil - correct answer ✔✔ DNA is overwound
negative supercoil - correct answer ✔✔ DNA is underwound
what type of coil do most eukaryotes, bacteria, and most archea possess? - correct answer ✔✔
negatively supercoiled DNA.
Helps for gene expression
what do archea living in acid at high temperatures possess? - correct answer ✔✔ positively
supercoiled becuase the companted DNA helps keep it from denaturing into single strands
topoisomerasses - correct answer ✔✔ enzymes that change DNA supercoiling
type I topoizomerases - correct answer ✔✔ removes supercoils
cleave one strand of DNA, allows rotation
type II topoisomerases - correct answer ✔✔ -adds supercoils
-cleave both strand of DNA
,DNA gyrase - correct answer ✔✔ some type of Type II topo.
targeted by quinolone anotibiotics like ciprofloxacin
without it, cells are killed bc they cant supercoil their DNA.
origin of replication - correct answer ✔✔ replication in bacteria begins here
oriC
termination sites - correct answer ✔✔ ter
where replication ends, located opposite to the origin
Dna A - correct answer ✔✔ initiation protein
increases in concentration as cell grows, binds to DNA for replication
DnaB - correct answer ✔✔ helicase, helps DNa unwind as its being unwound
DNA primase - correct answer ✔✔ synthesis of RNA primer, primes DNA by laying down short
RNA primer
DNA Pol III - correct answer ✔✔ major replication enzyme, has proof reading activity. Can
recognize mistakes in DNA. exonuclease proof reading activity
DNA Pol I - correct answer ✔✔ replaces RNA primer with DNA
DNA gyrase - correct answer ✔✔ relieves DNA supercoiling
sliding clamp - correct answer ✔✔ tethers DNA pol to the DNA to prevent it from falling off.
, termination of replication - correct answer ✔✔ ter sites are recognized by machinery
replicating. the two replicated chromosomes are linked together and you need a topo ro unlink
them.
what ter sites deals with replication forks moving clockwise? - correct answer ✔✔ Replication
forks moving clockwise are trapped by terJ, terG, terF, terB, and terC.
what ter sites deal with replication forks moving counter clockwise? - correct answer ✔✔
Counterclockwise-moving forks are trapped by terA, terD, and terE.
topoisomerase IV - correct answer ✔✔ after replicating and separating at ter sites. the plasmids
are stil looped together -linked chromosome catenane. so to unlink these, topo IV comes in and
resolutes it.
Xer C and Xer D - correct answer ✔✔ do the same as topo, they are enzymes that recognize a
specific site called dif on both DNA molecules and catalyze a series of cut and rejoining steps
that essentially pass one molecule through the other.
are plasmids supercoiled? - correct answer ✔✔ yes, negatively supercoiled like circular
chromosomes
two ways that DNA can interact with bacterial genomes - correct answer ✔✔ plasmids
bacteriophages
how to plasmids replicate? - correct answer ✔✔ autonomously, they have their own machinery
bidirectional replication vs rolling-circle - correct answer ✔✔ rolling circle moves in one
direction
answered graded A+
genome - correct answer ✔✔ genetic information that defines an organism
what do microbial genomes consist of? - correct answer ✔✔ one or more DNA chromosomes
that are usually circular, some linear.
plus plasmids that are usually circular but can be linear
vertical transmission - correct answer ✔✔ from parent to child gene transfer
horizontal transmission - correct answer ✔✔ transfer of pieces of DNA from one cell to another
structural gene - correct answer ✔✔ produces a functional RNA ("coding DNA").
-mRNA which encodes a protein
-rRNA, tRNA, small noncodingRNA
DNA control sequence - correct answer ✔✔ REGULATES THE EXPRESSION OF A STRUCTURAL
GENE
-DOES NOT ENCODE AN RNA
what is e.coli's genome size? - correct answer ✔✔ 4,600 kb(4 million base pairs) pair
chromosome, no plasmid though. humans have 3 billion kb for comparison
range of genome size in bacteria and archea chromosomes? - correct answer ✔✔ 460- >9000 kb
,operon - correct answer ✔✔ unit that contains genes with related functions that need to be
expressed together. has like 3 genes with one promotor that makes three proteins
(polycistronic)
regulon - correct answer ✔✔ different genes or operons controlled by the same transcription
factor. regulates synthesis of sigma factor that directs expression of all the genes
regulation of genes - correct answer ✔✔ control protein (transcription factor) will bind to
different places in the genome to coordinate transcription
positive supercoil - correct answer ✔✔ DNA is overwound
negative supercoil - correct answer ✔✔ DNA is underwound
what type of coil do most eukaryotes, bacteria, and most archea possess? - correct answer ✔✔
negatively supercoiled DNA.
Helps for gene expression
what do archea living in acid at high temperatures possess? - correct answer ✔✔ positively
supercoiled becuase the companted DNA helps keep it from denaturing into single strands
topoisomerasses - correct answer ✔✔ enzymes that change DNA supercoiling
type I topoizomerases - correct answer ✔✔ removes supercoils
cleave one strand of DNA, allows rotation
type II topoisomerases - correct answer ✔✔ -adds supercoils
-cleave both strand of DNA
,DNA gyrase - correct answer ✔✔ some type of Type II topo.
targeted by quinolone anotibiotics like ciprofloxacin
without it, cells are killed bc they cant supercoil their DNA.
origin of replication - correct answer ✔✔ replication in bacteria begins here
oriC
termination sites - correct answer ✔✔ ter
where replication ends, located opposite to the origin
Dna A - correct answer ✔✔ initiation protein
increases in concentration as cell grows, binds to DNA for replication
DnaB - correct answer ✔✔ helicase, helps DNa unwind as its being unwound
DNA primase - correct answer ✔✔ synthesis of RNA primer, primes DNA by laying down short
RNA primer
DNA Pol III - correct answer ✔✔ major replication enzyme, has proof reading activity. Can
recognize mistakes in DNA. exonuclease proof reading activity
DNA Pol I - correct answer ✔✔ replaces RNA primer with DNA
DNA gyrase - correct answer ✔✔ relieves DNA supercoiling
sliding clamp - correct answer ✔✔ tethers DNA pol to the DNA to prevent it from falling off.
, termination of replication - correct answer ✔✔ ter sites are recognized by machinery
replicating. the two replicated chromosomes are linked together and you need a topo ro unlink
them.
what ter sites deals with replication forks moving clockwise? - correct answer ✔✔ Replication
forks moving clockwise are trapped by terJ, terG, terF, terB, and terC.
what ter sites deal with replication forks moving counter clockwise? - correct answer ✔✔
Counterclockwise-moving forks are trapped by terA, terD, and terE.
topoisomerase IV - correct answer ✔✔ after replicating and separating at ter sites. the plasmids
are stil looped together -linked chromosome catenane. so to unlink these, topo IV comes in and
resolutes it.
Xer C and Xer D - correct answer ✔✔ do the same as topo, they are enzymes that recognize a
specific site called dif on both DNA molecules and catalyze a series of cut and rejoining steps
that essentially pass one molecule through the other.
are plasmids supercoiled? - correct answer ✔✔ yes, negatively supercoiled like circular
chromosomes
two ways that DNA can interact with bacterial genomes - correct answer ✔✔ plasmids
bacteriophages
how to plasmids replicate? - correct answer ✔✔ autonomously, they have their own machinery
bidirectional replication vs rolling-circle - correct answer ✔✔ rolling circle moves in one
direction
