AP Bio Gene Control and Biotechnology

When DNA is compacted by histones into 10 nm and 30 nm fibers, the DNA is unable to interact with proteins required for gene expression. Therefore, to allow for these proteins to act, the chromatin must constantly alter its structure. Which processes contribute to this dynamic activity?

• methylation and phosphorylation of histone tails

• nucleotide excision and reconstruction

Altering patterns of gene expression in prokaryotes would most likely serve the organismʹs survival in which of the following ways?

• allowing the organism to adjust to changes in environmental conditions

• organizing gene expression so that genes are expressed in a given order

• allowing environmental changes to alter the prokaryoteʹs genome

Tags

NGSS.HS-LS3-2

NGSS.HS-LS4-2

This can inhibit transcription by blocking the binding of positively acting transcription factors to the DNA:

• enhancer

• promoter

• repressor

The segment of DNA shown in the figure has restriction sites I and II, which create restriction fragments A, B, and C. Which of the gels produced by electrophoresis shown below best represents the separation and identity of these fragments?

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Which project is MOST LIKELY to interest a scientist working at a biotechnology company?

• study and reconstruction of fossilized bones

• conservation of key species within ecosystems

• development of genetically modified corn plants

• prevention of sewage leaking into water supplies

Tags

NGSS.HS-LS3-2

Where does RNA polymerase bind to DNA?

• at an activator site

• on the coding gene sequence

• at a promoter region

• downstream of the coding sequence

• Where the RNA primer is placed

Which of the following occur during RNA processing? (more than 1 answer applies)

• exons can be removed

• spliceosomes remove introns

• a poly-A tail and GTP cap are added

• DNA helicase unzips DNA

• activator sequences initiate transcription

Bacterial cells that contain pGal will fluoresce blue under ultraviolet light. Which of the following is the most likely outcome of replacing the lacA gene in the E. coli lac operon with the gene encoding pGal?

• When lacY and lac Z are breaking down and transporting lactose, the bacteria will fluoresce blue under ultraviolet light

• lacZ will only produce the enzyme for breaking down galactose in the presence of ultraviolet light

• the repressor enzyme will only be able to bind to the operator under the presence of lactose

• When the regulatory gene is stimulated by lactose, it will cause the gene to fluoresce blue

• All structural genes downstream from the placement of lacA will be inhibited due to this substitution mutation.

Tags

NGSS.HS-LS1-1

NGSS.HS-LS3-1

What kind of chemical bond is found between paired bases of the DNA double helix?

• hydrogen

• ionic

• covalent

What is meant by the description ʺantiparallelʺ regarding the strands that make up DNA?

• The 5ʹ to 3ʹ direction of one strand runs counter to the 5ʹ to 3ʹ direction of the other strand.

• One strand is positively charged and the other is negatively charged.