HSC Biology: DNA Sequencing and Profiling

This flashcard set covers the key terminology and processes of DNA sequencing, profiling, and amplification as discussed in the HSC Biology module on heredity.

DNA sequencing

The process of determining the sequence of nucleotide bases in a piece of DNA.

Human genome

The whole sequence of bases on all of the chromosomes in an organism.

Sanger sequencing

A technique developed by Fred Sanger's group that uses dideoxynucleotides to create terminal ends that stop DNA polymerization to map base sequences.

Dideoxynucleotides (ddNTPs)

Modified nucleotides that lack a hydroxyl group at the $3'$ position, acting as a "poisoned end" that blocks further polymerization.

Polymerase Chain Reaction (PCR)

An important reaction used to amplify or increase the amount of DNA through repeated cycles of denaturing, annealing, and extension.

Denaturing

The first process in PCR where DNA is heated to $95^{\circ}C$ to split the bonds between bases and separate the two strands.

Thermophiles

Extremophiles found in hot springs whose enzymes can withstand high temperatures, allowing them to be used in the PCR process.

Annealing

The process in PCR where temperature is adjusted to allow forward and reverse primers to bind to the separated DNA strands.

Primers

Short sections of DNA that bind to the separated strands to indicate where the polymerase should start and end copying.

DNA profiling

Also known as DNA fingerprinting, a technique used to identify individuals based on unique inheritance patterns in their DNA sequence.

Variable Number Tandem Repeats (VNTR)

Sequences of non-coding "junk DNA" that are repeated over and over, with the number of repeats varying between individuals.

Restriction enzymes

Proteins used to cut DNA at a particular, specific base sequence.

Gel electrophoresis

A technique that uses an electric field to separate DNA fragments in a gel based on size, where smaller particles move faster and further toward the positive terminal.