Final WGU BioChem OA Review Questions and Answers
Males and Females are equally affected – Autosomal
The process of copying DNA in the lab. – Polymerase Chain Reaction (PCR)
Template DNA, Nucleotides (dNTPS), DNA Polymerase, and DNA Primers. – What is
needed for Polymerase Chain Reaction?
Denaturing, Annealing, Elongating – *What are the three steps of a Polymerase Chain
Reaction (PCR)?
Denaturing (DNA is heated up to separate it) – *What is the first step of a Polymerase
Chain Reaction?
Cooling the Polymerase Chain Reaction. Primers stick to the DNA that you want to copy
and ADD DNA Polymerase – *What is Annealing?
The Polymerase Chain Reaction is heated and DNA Polymerase adds nucleotides to
build a new DNA strand. – *What is elongating?
Ligase – What is NOT involved in PCR?
It is used to repair damage to bases caused by harmful molecules by removing the base
that is damaged and replacing it. #1 GLYCOSYLASES see the damaged DNA. #2 DNA
Polymerase puts the right one back #3 DNA Ligase seals it. – What is base excision
repair (BER)?
DNA Glycolysase sees the damage and removes it, DNA polymerase puts the tight
base back, DNA ligase seals it back up. – What are the 3 steps in base excision repair?
1 – How many nucleotides does base excision repair remove?
Mismatch Repair (MMR). It is the only one to occur during REPLICATION – DURING
THE PROOFREADING – What is it called when a large section of the nucleotide is
removed from the DNA so that DNA polymerase can try again? (This corrects DNA
damage)
Mismatch Repair (MMR) repairs errors such as G with T instead of G with C. DNA
Polymerase fixes it. This happens during replication and MMR removes a large section
of the nucleotide from the DNA and DNA Polymerase tries again. – What repairs a base
mismatch?
When DNA polymerase takes an individual nucleotide and matches them to the parental
sequences to ensure a correct pair. (it must bind with RNA primer to work). ie: DNA
Polymerase binds to DNA to make RNA – What is DNA Transcription?
CLEANS damage caused by things such as UV rays and repairs it. A large section of
nucleotides are removed, including the damaged portion, along with a few on each side.
It is then replaced by DNA polymerase. – What is NecleoTIDE repair
It repairs double stranded breaks (last effort) by copying another strand of DNA and
replacing it completely. – What is Homologous Recombination?
Another last effort to repair a double strand break by putting the ends back together
before making sure they are correctly copied. This can lead to deletions/insertions
(frameshift mutations). – What is Non-Homologous Recombintaion?
It must bind to RNA primer – What does DNA Polymerase bind to in order to make RNA
TRANSCRIPTION DNA take the individual nucleotide and match them to the
PARENTAL sequences to ensure a correct pair.
introns (non-coding region) are removed and exons (coding region) joined to form a
contiguous coding sequence. – What happens during RNA splicing to generate a mature
RNA molecule?
The ability to turn genes on and off – What is Gene Expression?
The study of changes in organisms caused by modification of gene expression NOT
alternation of the gene code. – What is epigenetics?
Where a DNA molecule wraps around histone proteins to form tight loops called
nucleosomes. These nucleosomes coil and stack together to form fibers called
chromatin. (genes are ON if the nucleosomes are wide spread and OFF if the genes are
tightly packed) – What is packaging of DNA?
Polymerase – What is needed for DNA replication?
A point mutation in a sequence of DNA (change in one nucleotide) that results in a
premature STOP codon – *What is NonSense Mutation
A mutations in DNA that do not have an observable effect on the organism’s phenotype.
(1 neucleotide changes but it codes for the same amino acid) – *What is a Silent
Mutation?
A point mutation in which a single nucleotide change results in a codon that codes for a
DIFFERENT amino acid. – *What is a Missense Mutation?