Assume researchers are able to isolate the intact mRNA for a gene called qrs. The qrs mRNA isolated from the cheek cells was 500 nucleotides longer than the qrs mRNA isolated from the shoulder muscle of the same person. What is an explanation for this observation? O the poly A tail is shorter in the shoulder muscle O the precursor mRNAs are spliced differently in the two cell types O an exon was duplicated in the cheek cell transcription O the two cell type use different start codons

73Dicer catalyzes Sequence-dependent single-stranded RNA cleavage. Yesorno 74Amino acid-coding regions within eukaryotic genes may be interrupted by ___________ regions. A.noncodingb.long terminal repeatc.split geneD.enhancer 75Which of the following cleaves the N-terminal methionine from polypeptides?A.Methionine isomeraseb.Methionine aminopeptidasec.Methionine carboxylaseD.Methionine transferase

Many regions of non-coding eukaryotic DNA previously thought to be "junk" are now known to contain sequence elements important to regulating gene expression. What approach can be used to identify important non-coding regulatory regions when annotating a newly sequenced genome? O comparing CDNA to genomic DNA to validate that the gene is expressed O identifying restriction enzyme recognition sequences in the genome O phylogenetic footprinting to identify conserved non-coding sequences O searching for start/stop codons and splice recognition sites that predict where a gene might be located

Some exons in the human genome are quite small (lessthan 75 bp long). Identification of such “microexons” isdifficult because these distances are too short to reliablyuse ORF identification or codon bias to determine ifsmall genomic sequences are truly part of an mRNAand a polypeptide. What techniques of “gene finding”can be used to try to assess if a given region of 75 bpconstitutes an exon?