Ch. 20

The photograph shows female tortoiseshell cats Rainbow and CC (CC is Rainbow’s clone). Why is CC’s coat pattern different from Rainbow’s given that CC and Rainbow are genetically identical?

• random X chromosome inactivation

• heterozygous at coat color gene locus

• environmental effects on gene expression

• all of the above

Tags

NGSS.HS-LS3-1

NGSS.HS-LS3-2

Which is an incorrect statement about STRs (short tandem repeats)?

• They are tandemly repeated units of 5- to 10-nucleotide sequences
• The number of repeats is polymorphic from person to person
• Two alleles of an STR may differ in an individual
• They occur in specific regions of the genome
• PCR is used to amplify particular STRs

Which of the following is not a correct statement about third-generation sequencing?

• A single DNA molecule is sequenced on its own
• Different bases interrupt an electric current for a particular length of time
• DNA moves through a small nanopore
• DNA must be cut into fragments or amplified

Place the steps in a cycle of PCR (polymerase chain reaction) in the correct order: Annealing—Cool to allow primers to form hydrogen bonds with ends of target sequence.<br />Extension—DNA polymerase adds nucleotides to the 3 end of each primer.<br />Denaturation—Heat briefly to separate DNA strands.

• denaturation, annealing, extension
• denaturation, extension, annealing
• annealing, extension, denaturation
• extension, denaturation, annealing
• annealing, denaturation, extension

Which of the following tools and/or techniques would not be suitable as part of the molecular cloning of a particular gene?

• restricton enzyme
• plasmid
• CRISPR-Cas9
• PCR
• DNA ligase

Which of the following techniques would not be suitable for determining the presence of a specific mRNA in a tissue sample?

• RT-PCR
• RNA interference
• RNA-seq
• microarray

The coding strand of the human cancer gene BRCA1 contains the sequence 5′ ATG GAT TTA TCT GCT. What would be a suitable probe sequence to detect its mRNA expression via hybridization?

• 5′ ATG GAT TTA TCT GCT
• 3′ ATG GAT TTA TCT GCT
• 5′ AGC AGA TAA ATC CAT
• 3′ AGC AGA TAA ATC CAT
• all of the above

In order for PCR to work, what must be true about the orientation of the two primers relative to the template DNA?

• The primers must be complementary to each other and to the template
• The primers’ 5′ → 3′ orientations must go in the same direction when bound to the template
• The primers’ 5′ → 3′ orientations must point toward each other when bound to the template
• The primers’ 5′ → 3′ orientations must point away from each other when bound to the template

During the synthesis of cDNA, what is the order of the molecules that are used and/or created (ss = single stranded; ds = double stranded)?

• ssmRNA → RNA:DNA hybrid → ssDNA → dsDNA
• dsDNA → RNA:DNA hybrid → ssDNA → ssmRNA
• ssmRNA → ssDNA → RNA:DNA hybrid → dsDNA
• ssmRNA → RNA:DNA hybrid → dsDNA → ssDNA
• ssDNA → dsDNA → RNA:DNA hybrid → ssmRNA

Which of the following describes the key difference between embryonic stem (ES) cells and adult stem cells?

• Adult stem cells are more highly pluripotent than ES cells
• ES cells are more highly pluripotent than adult stem cells
• ES cells are longer lived than adult stem cells
• ES cells are made by deprogramming adult stem cells
• Adult stem cells are made by deprogramming differentiated ES cells