Solution to Question 7: Key processes of living systems
The following table summarizes the terms in the context of regulation of gene expression
(based on Campbell Biology, 8th Edition):
Term
Activation
Catabolite repression
Constitutive
pression
ex-
Gene expression
Leaky expression
Negative
tion
regula-
Positive regulation
Repression
Transcription
Translation
This process refers to
The process by which a regulatory protein (activator)
increases the rate of transcription by facilitating RNA
polymerase binding to the promoter.
Inhibition of alternative catabolic pathways (e.g., lactose metabolism) when a preferred energy source (like
glucose) is present.
Continuous expression of a gene, independent of regulation or environmental conditions.
The overall process by which genetic information in
DNA directs the synthesis of functional products (proteins or RNAs).
Low-level, basal transcription of a gene even under repressed conditions.
Regulation where a repressor protein binds to DNA and
prevents transcription.
Regulation where an activator protein binds to DNA
and stimulates transcription.
The process where transcription of a gene is reduced or
prevented, usually by a repressor protein.
The process of synthesizing RNA from a DNA template
by RNA polymerase.
The process of synthesizing a polypeptide chain (protein) from an mRNA template using ribosomes.
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