Chapter 3 (Gene Structure)- Experiment 1 Reading Flashcards
The human genome contains _____ base pairs. Coincidentally, the maize genome is approximately the same size.
2.5 Billion
Define Genome Annotation
The process of giving meaning to those billions of Gs, As, Ts, and Cs. A combination of experimental evidence and computer predictions is used to annotate genomes.
In this class, we will use a computer tool called the _____ for genome annotation.
DNA Subway
The _____ will be used to generate experimental data for the computer annotations.
PCR
What is the heating of the DNA strands called?
Denaturation HD
What is the cooling of the stands to allow the two primers to base pair to the primer-binding sites?
Annealing
Explain the process of how PCR makes copies of the desired area.
The PCR specifically copies a target DNA sequence. There’s double stranded DNA containing the target sequence. Two primers have sequences complementing primer-binding sites at the 3’ ends of the target gene on the two strands. The strands are separated by heating (CALLED DENATURATION); then cooled to allow the two primers to base pair to the primer-binding sites (CALLED ANNEALING). Together, the primers thus flank the targeted sequence. After the temperature is raised, Taq polymerase then synthesizes the first set of complementary strands (CALLED EXTENSION). These first two strands are of varying length, because they do not have a common stop signal. They extend beyond the ends of the target sequence as delineated by the primer-binding sites. Put very simply, you go through the process of Denaturation, annealing, and extension many-many times.
How is cDNA made? (Complementary DNA)
It is synthesized from mRNA.
In order to determine gene structure, one could find the location of exons by comparing the sequence of spliced mRNA to the sequence of genomic DNA. Unfortunately, this simple approach is not possible because it is very difficult to directly determine the sequence of RNA molecules. Instead, scientists first synthesize a DNA copy of mRNA using the enzyme _____.
Reverse Transcriptase
Define Reverse Transcriptase
A DNA polymerase that uses RNA instead of DNA as a template.
What is the DNA synthesized by reverse transcriptase called?
Complementary DNA (cDNA)
Define Amplicon
A piece of DNA or RNA that is the source and/or product of amplification or replication events (in this case, the result of PCR).
How can amplicons be visualized?
They can be visualized by agarose gel electrophoresis and, if desired, the resulting bands can be isolated and mailed to a company for sequencing.
