Te correct answer is 3. An origin of replication is a base sequence in the DNA at which the replication of DNA is initiated by the DNA polymerase.
B. A DNA molecule possesing an origin of replication and capable of of replicating itself in the host cell is called a:
The correct answer is 2. A cloning vector is a DNA molecule possesing an origin of replication and capable of replicating itself in the chosen host cell.
C. One of the two most commonly used cloning vectors are the viruses or bacteriophage DNA, the other ones are called _________.
The correct answer is 4. Plasmids are small (1mil-200mil mw) extrachromosomal, double-stranded circles of DNA molecules that can autonomously replicate in the host cell. Most of the presently used plasmids are artificially modified to give the desired properties that are useful for cloning in micoorganisms. Plasmids are generally identified by a code form like pab123, where p stands for plasmid, ab being the initials identifying the worker or laboratory responsible for isolating the plasmid and the number is the laboratory's code for that particular plasmid (e.g. pbr 322, psc 101, pmb1).
D. Enzymes that cut large DNA molecules into shorter fragments by cleaving specific nucleotide sequences on the DNA strand are called restriction ______
The correct answer is 2. Enzymes that cut large DNA molecules into shorter fragments or act like highly specific DNAses cleaving specific nucleotide sites on the DNA strand are restriction endonucleases. The recognition sites are the specific points that restriction endonucleases attact, also called as palindromes.
F. ______ are DNA sequences found within the coding regions of most eukaryotic genes that interupt the code for the gene product.
Correct answer is 2. Introns are the DNA sequences found within the coding regions of most eukaryotic genes that interupt the code for the gene product and those parts of the DNA sequence that code for the final protein are called exons. Several exons can be present in a single gene and each one is separated by introns.
G. The recognition sites on the DNA to which the RNA polymerase binds at the start of the transcription process is called a:
The correct answer is 4. These recognition sites on the DNA where the RNA polymerase binds to start transrcibing the amino acid sequence of the desired protein's DNA are called promoters.
H. For the translation of mRNA into protein to take place, the mRNA must carry a ________ in front of the gene to be translated.
The correct answer is 3. The mRNA must carry a ribosomal binding site (rbs) in front of the gene to be translated in order for translation to take place.