Which base alterations result in a frame shift mutation?
base insertion or deletions
Uses for Gel electrophoresis?
paternity testing, crime scene analysis - innocence vs guilty.
What are the 3 types of genes involved in cancer?
Oncogenes(tumour-genes), tumour suppression genes and DNA repair genes
Why is the bond between the base pairs weak?
so that they can be separated easily then replicated.
What does the tertiary structure refer to?
the 3D shape of the protein after it has been folded
Explain Gel electrophoresis.
DNA is injected into wells, the gel is placed in a buffer solution, there is 2 electrodes & a current is run through it, separating DNA based on size and charg.
What is a gene?
short segments coding for particular characteristic or trait
List the 3 types of base alterations that can occur?
Substitution, insertion or deletion
List 2 factors affecting gene expression
Gender, chemicals, temperature and products of other genes
What causes cancer?
Uncontrolled cell division/
Which 2 organelles in Eukaryotes posses extra DNA?
Mitochondria and Chloroplasts
Define plutipotent
can develop into any kind of human cell
What is cell differentiation?
the process by which cells with identical DNA become varied in structure and function
What does the secondary structure of a protein refer to?
the intermediates before it folds into 3D structure - ie alpha helices and beta pleated sheets.
Explain the process of PCR
temp up to 90 degrees DNA separates, temp lowered to 60 - primers added and bind to target regions, temp raised to 72 - DNA polymerase begins building strands
What is a silent mutation?
a change in base pairs leading to no noticeable effect
names 2 types of regulatory proteins.
Activators and repressors
What does the quaternary structure refer to?
two or more polypeptide chains (tertiary structures) chemically bonded.
What does a codon code for?
An amino acid
Explain semi-conservative DNA replication
helicase unwinds the double helix, DNA polymerase binds and uses free nucleotides to build the complementary strand from the exposed template
What is CRISPR-Cas9?
1. Guide RNA binding, 2. DNA cleavage, 3. DNA repair
What is a missense mutation?
a change in a base pair leading to a change in 1 amino acid in a polypeptide chain
Define multipotent
can develop into particular types - only some
What is a codon?
3 base pairs on the mRNA strand
What is a mutation?
A direct and permanent change to the sequence of DNA bases itself
Explain the process of transcription
Helicase unwinds the double helix, RNA polymerase builds the mRNA strand from free nucleotides and this leaves the nucleus and travels to the ribosome
State 2 types of inhibitors and how they work.
Competitive - bind to the active site blocking substrates, non-competitive bind to the allosteric site altering the shape of the active site.
What does enzymes do to rates of reaction and how?
they speed up the rate of reaction, by bringing together substrates or breaking them down through the lowering of activation energy
What is DNA methylation?
is a process which involves the addition of a methyl group (CH3) to the DNA strand (commonly to cytosine)