Biochem Exam 2
Nucleoside
1 base and 1 sugar
Nucleotide
1 base, 1 sugar, 1 phosphate group
How many pairs of autosomes does the human genome have?
22
What group (or atom) of the nucleotide base is esterified to a phosphate group to bind that nucleotide to the next one?
3' OH group
In DNA replication, the new strand always grows in the _______ direction.
5-3
Plasmids-
A plasmid is a small, extrachromosomal DNA molecule within a cell that is physically separated from chromosomal DNA and can replicate independently and are present in all bacterium's.
The first three bases of the six-base recognition cleavage site of HindIII are AAG.What is the complete sequence of this 6-bp site?
AAGCTT
Due to _________________, genes encode for more than one protein.
Alternate Splicing
What statement about the palindromic sequence is right? 1.It is the DNA sequence that reads the same from right to left as it does from left to right. 2. It contains a twofold axis of symmetry. 3. It is the specific sequence of four to eight base pairs. 4. A restriction enzyme hydrolyzes hydrogen bonds in this region
Answer Unknown
BP in DNA/RNA
Answer unknown
What bonds link bases to sugars in nucleotides?
Beta-glycosidic bond
Helix Diameter:
DNA A- 19 Angstroms DNA B- 19 Angstroms DNA Z- 19 Angstroms
What is NOT included in the PCR mixture?
DNA Ligase
What enzyme catalyzes the step-by-step addition of deoxyribonucleotide units to a DNA strand on the basis of template DNA?
DNA Polymerase
Sanger DNA sequencing
DNA SEQUENCE FOR CHAIN TERMINATION PCR, SIZE SEPARATION BY GEL ELECTROPHORESIS, GEL ANALYSIS & DETERMINATION OF DNA SEQUENCE.
Which step is NOT included in the technique called Southern blotting?
Denature the DNA (usually while it is still on the gel)
To begin synthesis, DNA polymerases require a primer with a free 5 -OH group that is already bound to the template strand.
F It is the 3 side.
This technique allows the creation of proteins with unique characteristics and activities.
Folding and intramolecular bonding
C- Cytosine
G- Guanine
What advantage can be gained by splicing together portions of 2 different genes?
IT ALLOWS FOR THE CREATION OF PROTEIN WITH UNIQUE characteristics.
What is the difference between lytic and lysogenic pathways that λ phage uses for multiplying?
In the lysogenic pathway, the phage enters the cell while in the Lytic pathway, the phage destroys the cell.
Although the right-handed double helix is the most well-known DNA structure, DNA can also form:
Left Handed
What enzyme catalyses the formation of a phosphodiester linkage at a break in the DNA strand.
Ligase
PCR-
Polymerase chain reaction is a method widely used to rapidly make millions to billions of copies of a specific DNA sample, allowing scientists to take a very small sample of DNA and amplify it to a large enough amount to study in detail.
What statement about polyacrylamide gels and agarose gelsisfalse
Polysa
What component is strongly required by DNA polymerases but is NOT needed by RNA polymerase?
Primer
Introns nearly always begin with GU and end with AG that is preceded by the ________________.
Pyridine rich tract
What enzyme is capable of synthesizing DNA from an RNA template?
Reverse Transcriptase/RNA dependent DNA Polymerase.
How many chiral carbon atoms do ribose and deoxyribose contain in nucleic acids?
Ribose- 4 Chiral Carbons, Deoxyribose- 3 Chiral Carbons
In bacterial mRNA, the intimidating AUG codon is preceded several nucleotides away by a purine-rich sequence called the ______________________________, which base pairs with a complementary source in an rRNA.
Shine Dalgarno sequence
Every 3 base codon encodes a
Specific Amino Acid
Choose the right temperature for each step of the PCR cycle (the cycles have to be in the right order).
Strand Separation- Heating to 95 degrees, Hybridization of primers- Cooling to 54 degrees, DNA synthesis- Heating to 72 degrees.
The feature of DNA structure that was NOT deduced by Watson and Crick from the DNA diffraction patterns.
Supercoiling
A- Adenosine
T- Thymine
The base composition of the DNA includes 28% G and 26% A. How much T would be in the RNA synthesized from this DNA template?
T=26%
What is the nucleotide sequence on the DNA template strand that yields the CUA codon for leucine?
TAG
The temperature at which half of the DNA helical character is lost is referred to as:
TM
The DNA fragment was inserted into the specific plasmid. What do plasmid and the DNA fragment have in common?
The same sticky ends.
Ti plasmids stand for:
Tumor Inducing Plasmids
The chemical forces that contribute to the stability of the DNA due to the base stacking present in the DNA helix are:
Vanderwaals
What are the common promoter regions found in eukaryotic genes?
a TATA box at about -25 and often a CAAT box at about -75
Restriction Enzyme:
a protein produced by bacteria that cleaves DNA at specific sites along the molecule.
Exons-
a segment of a DNA or RNA molecule containing information coding for a protein or peptide sequence.
The process of DNA renaturation after melting is called
annealing
point mutation
gene mutation in which a single base pair in DNA has been changed
A noncoding region within a gene is known as a(n):
intron
Which molecules are used as a template in translation?
mRNA
Yeast chromosome
no operon
Ribosomes are composed of:
rRNA and proteins
What is CORRECT concerning the adaptor molecule tRNA?
tRNA contains an anticodon sequence that serves as the template recognition site
What can be used to add nucleotides to the 3 ends of DNA?
terminal transferase
Homologous recombination is
the process in which two DNA molecules with a strong sequence similarity exchange segments.
Met and Trp codons are used to design DNA probes because
they do no degenerate and have single codons
