Question

QUESTION 18

Which of the following enzymes will produce a blunt end (the cut site is indicated by the * in the recognition sequence)?

		NsiI (ATGCA*T)
		EcoRV (GAT*ATC)
		TaqI (T*CGA)
		EagI (C*GGCCG)

  

QUESTION 19

Which of the following is a functional element of a plasmid?

		drug-resistance gene
		origin of replication
		sequence encoding a restriction endonuclease
		polylinker sequence

QUESTION 20

Next generation sequencing is much more efficient than the Sanger method because:

		it uses gel electrophoresis to resolve end-labeled strands of DNA, and it uses PCR amplification.
		it uses an RNA template instead of DNA.
		it uses gel electrophoresis to resolve end-labeled strands of DNA.
		it uses PCR amplification.

Answer 1

QUESTION 18 - answer: EcoRV (GAT*ATC)
Explanation: EcoRV is a type II restriction endonuclease isolated from certain strains of Escherichia coli. It is a commonly used restriction enzyme. It creates blunt ends.

QUESTION 19 - answer: origin of replication
Explanation: Plasmid is the techniques in chemistry which enable isolation and purification of cellular components, such as DNA, but practically this isolation is only feasible for relatively short DNA molecules. In order to isolate a particular gene from human chromosomal DNA, it would be necessary to isolate a sequence of a few hundred or few thousand basepairs from the other six billion basepairs of the human genome.
QUESTION 20 - answer : it uses gel electrophoresis to resolve end-labeled strands of DNA.

Explanatin: DNA sequencing is the process of determining the sequence of nucleotides. The most recent set of DNA sequencing technologies are collectively referred to as next-generation sequencing. Walter Gilbert developed another sequencing technology based on chemical modification of DNA and subsequent cleavage at specific bases. Because of its high efficiency and low radioactivity, Sanger sequencing was adopted as the primary technology in the “first generation” of laboratory. ext-generation sequencing is kind of like running a very large number of tiny Sanger sequencing reactions in parallel.
Applied Biosystems introduced the first automatic sequencing machine, adopting capillary electrophoresis which made the sequencing faster and more accurate.