Chapter 18 notes (test Flashcards
Are all an organism’s genes being expressed at the same time?
no, they can be turned on and off as needed
Both _________and____________ can control gene expression in response to ______________
prokariotic and eukaryiotic cells, changing environmental conditions
the regultaion of gene expression controls cell ________ in the proccess of _____________ developement
differentiation, embryological
Genes are turned on and off by starting or stopping what?
transcription
Operator
a single switch that control genes in bacteria
a single switch that controls genes in bacteria
operator
Operons
a unit of genetic function which consists of a promoter, operator, and genes
a unit of genetic function which consists of a promoter, operator, and genes
operon
Repressible operons
Transcription is usually on, but can be turned off or repressed
Transcription is usually on, but can be turned off or repressed
Repressible operons
Repressible operons usually function in ?
anabolic pathways
Repressor
inactive by itself, binds to the operator and blocks the RNA polymerase, a small protein that can turn the operon off
Regulatory gene
makes a specific protein to turn the operator off
corepressor
inactive by itself, binds to the repressor to activate it
Inducible Operons
Transcription is usually off, but can be turned on, or induced
Transcription is usually off, but can be turned on, or induced
inducible operons
inactive by itself, binds to the repressor to activate it
corepressor
inactive by itself, binds to the operator and blocks the RNA polymerase, a small protein that can turn the operon off
repressor
makes a specific protein to turn the operator off
regulatory genes
Inducible operons usually function in….
catabolic pathways
inducer
a small molecule that inactivates the repressor
Positive gene regulation
proteins bind to DNA and encourages transcription
a small molecule that inactivates the repressor
inducer
proteins bind to DNA and encourages transcription
positive gene regulation
Inducible operons usually function in….
catabolic pathways
inducer
a small molecule that inactivates the repressor
Positive gene regulation
proteins bind to DNA and encourages transcription
a small molecule that inactivates the repressor
inducer
Histone Modification
addition of acetyl groups
the loosing of the DNA to promote transcription
Chromatin Modification
a protein that binds to the promoter and stimulates transcriptoipn of genes , atract RNA polymerase
activator
Gene exoression may be regulated at what stage of DNA to Protein
any
Chromatin Modification
the loosing of the DNA to promote transcription
Histone Modification
addition of acetyl groups
the loosing of the DNA to promote transcription
Chromatin Modification
DNA Methylation
addition of mathyl groups, inactivates the DNA
Epigenetic inheritance
the inheritance of traits not directly involved in DNA
addition of acetyl groups
Histone Modication
addition of mathyl groups, inactivates the DNA
DNA Methylation
the inheritance of traits not directly involved in DNA
Epigenetic inheritance
control elements
segments of non-coding DNA, upsteam frmo the genes, binding sites for proteins called transcription factors
segments of non-coding DNA, upsteam frmo the genes, binding sites for proteins called transcription factors
control elements
enhancers
cites on DNA where activators bind that help control transcriptoin animation
cell type- specific transcription
gene expression varies from cell to cell because different activators are available in different cells
cites on DNA where activators bind that help control transcriptoin animation
enhancers
ncRNA
noncoding RNA, not involved with protein synthesis
miRNA, siRNA
prevent gene expression by 1)breaking down RNA 2) stop translation
mRNA Degradation
RNA is broken down in cytoplasm, after a few hours, days, or weeks
RNA is broken down in cytoplasm, after a few hours, days, or weeks
mRNA Degradation
Regulatory proteins can block attachment of ______ to ________thus preventing ___________
mRNA, ribosomes, translation
ncRNA
noncoding RNA, not involved with protein synthesis
DNA Methylation
addition of mathyl groups, inactivates the DNA
Epigenetic inheritance
the inheritance of traits not directly involved in DNA
addition of acetyl groups
Histone Modication
addition of mathyl groups, inactivates the DNA
DNA Methylation
the inheritance of traits not directly involved in DNA
Epigenetic inheritance
control elements
segments of non-coding DNA, upsteam frmo the genes, binding sites for proteins called transcription factors
segments of non-coding DNA, upsteam frmo the genes, binding sites for proteins called transcription factors
control elements
enhancers
cites on DNA where activators bind that help control transcriptoin animation
cell type- specific transcription
gene expression varies from cell to cell because different activators are available in different cells
cites on DNA where activators bind that help control transcriptoin animation
enhancers
Alternative RNA splicing
different mRNA molecules can be made from same portion of DNA
different mRNA molecules can be made from same portion of DNA
Alternative RNA splicing
mRNA Degradation
RNA is broken down in cytoplasm, after a few hours, days, or weeks
RNA is broken down in cytoplasm, after a few hours, days, or weeks
mRNA Degradation
Regulatory proteins can block attachment of ______ to ________thus preventing ___________
mRNA, ribosomes, translation
ncRNA
noncoding RNA, not involved with protein synthesis
miRNA, siRNA
prevent gene expression by 1)breaking down RNA 2) stop translation
miRNA, siRNA
prevent gene expression by 1)breaking down RNA 2) stop translation
