Which is not true about restriction enzymes? a. They cut RNA b. They evolved as a bacteria defense mechanism c. They can leave single-stranded overhanging sequences called Sticky ends d. They recognize a specific target sequence e.They cut DNA
Restriction enzymes do not cut RNA. answer: A
DNA restriction and modification systems are common mechanisms
by which bacteria protect their DNA from contamination by invading
or foreign DNA.
Many bacteria produce a restriction enyzme that cleaves foreign DNA
at a specific sequence.
For the bacteria to survive the presence of these enzymes, an
accompanying DNA modification system (such as adenine methylation
and cytosine methylation)
Type II restriction/modification systems consist of two separate
proteins:
1) a restriction endonuclease and
2) a separate methylase.
Note that Type I and III restriction/modification systems have both
activities included within one protein.
Restriction enzymes bind to and cleave double-stranded DNA at
specific sites.
Different restriction sites recognize different sequences.
Most type II restriction enzymes recognize symmetric sequences that
are 4, 5 or 6 base pairs in length.
A small minority of restriction enzymes recognize larger
sequences.
Some recognize somewhat non-symmetric sequences.
The site of cleavage within the recognition sequence can
produce
1) blunt ends,
2) overhanging 3 prime ends or
3) overhanging 5 prime ends.
The protruding single-strands can be united with similar ends to
readily produce recombinant molecules.
Isoschizomers are enzymes from different sources that target the
same target sequence.
Depending upon how the cleavage sites compare, the enzymes may or
may leave the same ends (compatible ends).
Often enzymes with a hexanucleotide recognition sequence
(6-cutters) will leave a 4 nucleotide overhang.
Other enzymes that recognize a different hexanucleotide sequence
that share the same central tetranucleotide motif may leave the
same ends (compatible ends).
For example: SalI (GTCGAC) and XhoI (CTCGAG) leave compatible ends
that once ligated, result in a site (GTCGAG) that is not cleaved by
either enzyme.
Which is not true about restriction enzymes? a. They cut RNA b. They evolved as a...
find the errors Restriction enzymes recognize specific DNA sequences and cut each strand of DNA at specific locations at the target sequence. The result of digesting a particular genome with a particular restriction enzyme is a collection of restriction fragments of defined length and composition. These can be used to generate restriction maps or create pieces with sticky ends. These sticky ends can be used to attach to other fragments that have sticky ends caused by cutting with a different...
Restriction endonucleases.... a) are used to cut RNA at defined sequences. b) can be used to create pieces of DNA with cohesive ends. c) have no specific sequence requirements for recognition or cutting. d) were identified as a protozoan defense mechanism against viruses. e) are used in standard DNA sequencing reactions.
DNA fragments cut by most restriction enzymes have: double-stranded complementary ends. either only sequences of Gs or only sequences of Cs. cuts made at random points along one of the strands. protruding sticky ends.
14. Restriction endonucleases are a. enzymes that restrict DNA synthesis b. enzymes that cut DNA in specific sequences c. nuclear proteins that are involved in transcription d. components of the ribosomes involved in protein synthesis 15. The first step in southern blotting is a. converting DNA into RNA b. cutting high molecular weight DNA into smaller pieces c. converting RNA into DNA d. radioactively labeling the DNA so it can be detected after the procedure is complete 16. The major...
please answer and explain each answer (2 points). Which of the following is cut by restriction enzymes? a. Double-stranded DNA b. Double stranded RNA c. Single-stranded DNA d. Single-stranded RNA (2 points). Which of the following is cut by Dicer? a. Double-stranded DNA b. Double stranded RNA d. Single-stranded RNA c. Single-stranded DNA
9. An alteration in the nucleic acid sequence in which a specific restriction endonuclease cuts can be detected by a. ELISA b. flow cytometry c. RFLP d. FISH 10. Which of the following techniques enables the identification of a particular sequence of nucleic acid on a cell or tissue? a. northern blot b. western Blot c. FISH d. southern blot 11. The polymerase chain reaction is used to a. convert RNA back into DNA b. amplify a target nucleic acid...
Which of the following statement(s) is(are) true about restriction enzymes? A)discovered in bacteria B)cleave the phosphodiester bond in the backbone C)cleave the peptide bond in the backbone D)produces random fragments E)recognizes specific sequences
1. A circular plasmid has two PmeI restriction sites. A PmeI restriction enzyme will cut this plasmid into two fragments. A. True B. False 2.In general, restriction enzymes that recognize four nucleotides have higher probability to produce more DNA fragments than those enzymes that recognize six nucleotides. A. true B. false 3. Which of the following sequences are palindromes? A. 5' TGGCCA 3' B. 5' GAAAAG 3' C. 5' CGATGG 3' D. 5' GACGAC 3' 4. Below are the possible...
Which statement best describes restriction enzymes? View Available Hint(s) Which statement best describes restriction enzymes? They randomly cut DNA molecules to generate numerous fragments. They are necessary for the polymerase chain reaction (PCR) to occur. They are important for cloning applications because they can be used to cut DNA at specific nucleotide sequences. They can cut only circular plasmid DNA.
please answer question numbe 2. Restriction endonucleases are bacterial enzymes that recognize, bind, and cut DNA strands at specific recognition sequences. They evolved to protect bacteria from bacterial viruses and are very useful for a wide variety of molecular biology applications. Some of the more common ones include EcoRI which recognizes the 6 bp sequence 5 'GAATTC 3' and cleaves the phosphodiester backbone after the G. Hind III_(AAGCTT), BamHI (G|GATCC), Pstl (CTGCAG), Not! (GC|GGCCGC), Ndel (CATATG) Kpnl (GGTAC^C), Bgl II...