1.1.5 DNA Part 2

Extraction and Replication

DNA Extraction

The process of releasing, isolating, and purifying DNA from the inside of the cells so it can be separated from proteins, lipids and other cellular material.

4 Steps to DNA Extraction

1. Break open the cell and nucleus

2. Purify the DNA of any cell proteins, cell waste, other organelles, cell membrane components, etc.

3. Bundle the DNA by adding alcohol. Clumps together in alcohol (dissolves in water). Adding alcohol to purified DNA makes it sold (white string) → Now that it’s visible it can easily be picked up for processing.

4. Clean the DNA of any proteins still attached. Histones are an example of a protein that the DNA may still be clinging to.

Precipitate

Solid, visible mass of DNA forming and separating out of a liquid solution when salt and alcohol are added.

PCR (Polymerase Chain Reaction)

Creates millions of copies of DNA from a small strand (laboratory technique for amplifying DNA in vitro. Uses a thermocycler, primers, DNA polymerase, and nucleotides.

Why is DNA heated in the third stage of PCR?

to allow DNA Polymerase to add free nucleotide bases

Why is DNA heated in the first stage of the Polymerase Chain Reaction (PCR)?

break hydrogen bonds

DNA and proteins are packaged into____________.

Chromosomes

Which of these makes DNA negative?

phosphate

In PCR, denaturation is the process that ________

causes complementary DNA strands to separate, break apart

Where is Taq Polymerase found naturally?

target DNA

The extraction buffer was made up of...

water, salt, soap

Restriction digestion means ________

the process of cutting DNA molecules into smaller pieces using restriction enzymes

A series of reactions that make multiple identical copies of DNA, using varying temperatures

(PCR) Polymerase Chain Reaction

In the Polymerase Chain Reaction (PCR), which is the correct sequence?

denaturing, annealing, extension

The correct order of the 4 main steps for DNA analysis are

1. DNA Extraction

2. PCR

3. Restriction Digest

4. Gel Electrophoresis

The purpose of the polymerase chain reaction (PCR) is to ______

produce millions of identical copies of a specific DNA sequence from a small amount of DNA

In PCR, extension is the step of the process that ________________

causes Taq polymerase to add complementary nitrogen bases to build the new DNA

Your DNA is related to another human by ______

99%

Why is DNA cooled in the second stage of PCR?

to allow the primers to bind

A segment of DNA is called a_______

gene

recognition sites are the _____

specific locations where the restriction enzymes cut the DNA strand

restriction enzymes are named for the specifc _________ that produced them

bacteria

Which is NOT an application of PCR?

replication of bacteria

restriction enzymes

molecular “scissors” that cut DNA in specific locations

anneal/annealing

two complementary strands of DNA pair up by hydrogen bonding to form a stable double-stranded helix

extension

copies and lengthens new DNA strands from the extracted template

What makes strawberries an ideal specimen for DNA extraction?

Contains a lot of DNA for extraction and analysis