BIOLOGY
ENZYMES
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
single-stranded DNA “overhangs” that can bind to complementary DNA
|
|
|
smooth cuts that are sticky due to the “goo” left behind by the enzyme
|
|
|
The two wires (black and red) on a gel box
|
|
|
The surface of the LB agar plates so that bacteria can grow
|
Detailed explanation-1: -A restriction enzyme is a DNA-cutting enzyme that recognizes specific sites in DNA. Many restriction enzymes make staggered cuts at or near their recognition sites, producing ends with a single-stranded overhang. If two DNA molecules have matching ends, they can be joined by the enzyme DNA ligase .
Detailed explanation-2: -A ‘sticky’ end is produced when the restriction enzyme cuts at one end of the sequence, between two bases on the same strand, then cuts on the opposite end of the complementary strand. This will produce two ends of DNA that will have some nucleotides without any complementary bases.
Detailed explanation-3: -Restriction endonucleases (13 out of 18 species used for the test) were certified to cleave single-stranded(ss)DNA. Such enzymes as AvaII, HaeII, DdeI, AluI, Sau3AI, AccII, TthHB8I and HapII were newly reported to cleave ssDNA.
Detailed explanation-4: -To join sticky ends DNA ligase enzyme is used which acts by catalyzing the formation of a phosphodiester bond. DNA ligases are called Molecular glue since these enzymes are used during replication for joining phosphodiester backbone, used in RDT for joining sticky ends, and also used in damage and repair cells.