DNA Structure and Replication
What is the base-pair rule in DNA?
Adenine pairs with Thymine
Guanine pairs with Cytosine
_______________ is the enzyme that creates hydrogen bonds between nucleotides on the DNA template strand and their complementary RNA nucleotides in a newly formed mRNA strand
What type of operon is the lac operon?
Inducible
The purpose of the Sanger Sequencing method is to
sequence DNA
Thymine makes up 13% of the nucleotides in a sample of DNA. Approximately what percent of the nucleotides in this sample will be cytosine?
37%
What happens to a pre-mRNA molecule after it has been transcribed, but before it leaves the nucleus (3 things!)?
- Removal of Introns
- Addition of poly-AAA Tail
- Addition of 5` Cap
What type of operon is the trp operon?
repressible
In recombinant DNA experiments, what is used to cut pieces of DNA, and what joins the resulting fragments to form recombinant DNA?
a restriction enzyme, DNA ligase
DNA replication results in two DNA molecules, each with one new strand and one old strand; This is considered _______________ replication.
semi-conservative
What are the 3 main steps of Translation?
Initiation
Elongation
Termination
Match the following terms to their roles in an operon.
(a) Lactose (d) Promoter
(b) Repressor (e) RNA polymerase
(c) Regulatory gene
Acts as an inducer in the Lac operon______
Binding site for RNA polymerase______
Codes for the repressor ______
Binds at the operator ______
Acts as an inducer in the Lac operon__A____
Binding site for RNA polymerase__D____
Codes for the repressor ___C___
Binds at the operator ___B___
What is the name of the enzyme used in PCR and why is it so special?
Taq Polymerase - High heat resistance
Match the following Enzymes with their role in DNA Replication:
Helicase ______
Topoisomerase _______
DNA Polymerase_____
Ligase _____
a. relaxes supercoiling in front of the replication fork.
b. synthesizes new strands of DNA
c. joins the fragments on the lagging strand.
d. unwinds the DNA strands.
Helicase ___D___
Topoisomerase ___A____
DNA Polymerase__B_
Ligase __C___
Given the following DNA identify the codon, anticodon and amino acid.
TAC
mRNA: AUG
tRNA: UAC
Amino Acid: Met
Both liver cells and lens cells have the genes for making the proteins albumin and crystalline. However, only liver cells express the blood protein albumin and only lens cells express crystalline, the main protein in the lens of the eye. Both of these genes have enhancer sequences associated with them.
The claim that gene regulation results in differential gene expression and influences cellular products (albumin or crystalline) is best supported by evidence in which of the following statements?
Liver cells possess transcriptional activators that are different from those of lens cells.
Liver cells and lens cells use different RNA polymerase enzymes to transcribe DNA.
Liver cells and lens cells possess the same transcriptional activators.
Liver cells and lens cells possess different general transcription factors.
1. Liver cells possess transcriptional activators that are different from those of lens cells.
In a transformation experiment, what is the point of using a plate with no antibiotic and bacteria with no plasmid? What does this plate tell you?
Bacteria is viable/functional
A student analyzed a newly discovered viral genome and found that the genome had the following nucleotide composition:
28% adenine 35% cytosine
20% thymine 17% guanine
Which of the following best describes the structure of the viral genome?
Double-stranded DNA
Double-stranded RNA
Single-stranded RNA
Single-stranded DNA
Single-stranded DNA
Identify the following types of mutations:
Leu --> Glu
Leu --> Leu
Leu --> STOP
Missense
Silent
Nonsense
The addition of _____________ groups to DNA causes it to remain highly compacted (not available for transcription).
The addition of _____________ groups to histones in chromatin allow it to uncoil and be available for transcription.
Methyl; Acetyl
In a Gel Electrophoresis experiment, the restriction enzyme cuts the DNA into the following fragment lengths:
17 (A), 2 (B), 37 (C)
What order would the fragments on the gel be from - to +? (Draw it if it is easier)
- - 37, 17, 2 - +