Unit 4 Quizizz

Gene expression might be altered based on post-transcriptional processing in eukaryotes rather than prokaryotes because of which of the following? 

• Eukaryotic mRNAs get 5' caps and 3' tails.
• Prokaryotic genes are expressed as mRNA, which is more stable in the cell.
• Prokaryotes use ribosomes of different structure and size.
• Eukaryotic exons may be spliced in alternative patterns.

If a cell were unable to produce histone proteins, which of the following would be expected to occur?

• There would be an increase in the amount of "satellite" DNA produced during centrifugation
• The cell's DNA couldn't be packed into its nucleus.
• Spindle fibers would not form during prophase.
• Amplification of other genes would compensate for the lack of histones.

What is the sequence of a peptide based on the mRNA sequence 5' UUUUCUUAUUGUCUU 3' ?

• leu-cys-tyr-ser-phe
• cyc-phe-tyr-cys-leu
• phe-leu-ile-met-val
• phe-ser-tyr-cys-leu

The strands that make up DNA are antiparallel. This means that

• the twisting nature of DNA creates nonparallel strands.
• one strand is positively charged and the other is negatively charged.
• the 5' to 3' direction of one strand runs counter to 5' to 3' direction of the other strand.
• base pairings create unequal spacing between the two DNA strands.

Which of the following molecules, when taken up by the cell, binds to the repressor so that the repressor no longer binds to the operator? 

• inducer 
• ubiquitin
• promotor
• repressor

What is a genome?

• the complete complement of an organism's genes
• a specific sequence of polypeptides within each cell
• a specialized polymer of four different kinds of monomers
• a specific segment of DNA that is found within a prokaryotic chromosome

The figure below represents the stained nucleus from a cheek epithelial cell of an individual whose genotype would probably be 

• XX
• XY
• XYY
• XXX

A researcher found a method she could use to manipulate and quantify methylation of DNA in embryonic cells in culture. One of her colleagues suggested she try increased methylation of C nucleotides in a mammalian system. Which of the following results would she most likely see? 

• increased chromatin condensation 
• decreased transcription of the selected genes 
• activation of histone tails for enzymatic function 
• decreased chromatin condensation

Which of the following descriptions of nucleotide triplets best represents a codon? 

• a triplet separated spatially from other triplets 
• a triplet that has no corresponding amino acid 
• a triplet at the opposite end of tRNA from the attachment site of the amino acid
• a triplet in the same reading frame as an upstream AUG

Metabolic pathways that release stored energy by breaking down complex molecules are known as 

• catabolic pathways
• anabolic pathways
• endergonic pathways
• bioenergetic pathways