Chapter 17 - Regulation and Mutations

Structural genes

________ are coding sequences that include the genetic code for the proteins needed to carry out the operon's function.

Promoters

________ are noncoding regulatory regions that act as RNA polymerase binding sites.

DNA

Mutations can occur as a result of environmental stimuli such as chemicals or radiation, or as a result of random mistakes in ________ replication.

Euchromatin

________ is DNA that is more loosely coiled around histone proteins, making it more accessible to RNA polymerase and resulting in higher gene expression in the ________.

Errors

________ in mitosis or meiosis can also result in mutations.

CAMP

________ binds to the catabolite activator protein (CAP), causing it to bind at a CAP binding site close to the promoter.

Hete

________ is formed when DNA in chromosomes is firmly coiled around histone proteins.

Epigenetic alterations

________ are reversible modifications to the nucleotides of the DNA sequence, such as nucleotide methylation (adding a methyl group)

full additional set of chromosomes

Aneuploidies that result in polyploids (an ________) in plants, on the other hand, might provide a benefit to the plant, making it more likely to survive.

Aneuploidy

________ can occur when homologous chromosomes fail to split during meiosis (an incorrect number of chromosomes)

Gene expression

________ may be affected by mutations in the DNA.

Hox

During development, the ________ gene, which codes for antennapedia, regulates the creation of legs in Drosophila.

lactose

If no ________ is present, the lac repressor protein binds to the operator, preventing RNA polymerase from transcribing the operon.

amino acid tryptophan

The ________ acts as a corepressor in the trp operon.

histone

The ________ proteins that surround DNA when it is packed into chromosomes can also be epigenetically changed by adding acetyl groups (acetylation)

trp repressor protein

The ________ can not bind to the operator sequence on its own; it must first be coupled to the amino acid tryptophan before it can bind to the operator sequence.

regulatory regions

Operators are noncoding ________ that act as repressor protein binding sites (a type of regulatory protein)

epigenetic alterations

In eukaryotes, ________ can also impact gene expression.

Lactose

________ binds to the lac repressor protein, altering its structure so that it can no longer bind to the operator sequence.