1. PCR

GENOME- DEFINITION

• total of all genetic material in an organism

INTRONS AND EXONS

• DNA that makes up chromosomes consists of billions of base pairs

• but coding regions of DNA that determine protein structures, only make up around 2% of that DNA

• EXONS- coding regions

• INTRONS- large, non coding regions of DNA

  • if these are found in genes they are removed from mRNA after transcription, before it is translated

DNA/GENE SEQUENCING

• analyse individual strands of DNA or individual genes

• gives order of bases that codes for a particular protein in cell

• can also be used to identify diff species of living organism

DNA PROFILING

• analyse patterns in non-coding areas of DNA and use them to identify individuals

PCR USES- LIST

• polymerase chain reaction used for:

  • genotyping

  • cloning

  • mutation detection

  • sequencing

  • forensic science, to identify criminals

  • test paternity

PCR USES

• PCR adapts natural process of DNA replication in cells, enabling us to produce larger samples from tiny traces of biological materials

• when tiny sample of DNA is increased using PCR to produce a large enough sample for analysis (amplification)

DEVELOPING PCR- ISSUE

• to separate DNA strands in PCR the sample DNA needed to be heated to around 90-95°C

• but DNA Polymerase is needed and would be denatured by a temp this high

DEVELOPING PCR- SOLUTION

• enzymes from a thermophilic bacterium that lives in hot springs is used

• enzymes in this bacterium are not denatured at high temps changes needed to allow for DNA replication

PCR- REQUIREMENTS

• DNA sample

• HEAT STABLE DNA POLYMERASE- enzyme that joins DNA nucleotides together

• DNA NUCLEOTIDES - Consisting of deoxyribose sugar, phosphate, and either an A,T,C or G base

• PRIMERS

• Thermal Cycler machine

PRIMERS

• short chain of DNA nucleotides- have a base sequence complementary to the ends of the DNA fragments

• mark where DNA fragment is to be extended/built/amplified

PCR- STEPS