DNA discover, replication, PCR & telomeres

Griffith's experiment

Reported in 1928 by Fredrick Griffith

genetic transformation

Taking DNA from one organism and putting it into another organism so they exhibit the trait.

Avery

MacLeod

Hershey-Chase Experiment

confirmed that DNA is the genetic material because only radiolabeled DNA could be found in bacteriophage-infected bacteria

Chargaff's Rule

A

double helix

two strands of nucleotides wound about each other; structure of DNA

DNA replication

DNA unzips into two parts and splits with the cell. In it's new home each side of the DNA strand attack to matching nucleotides to create 2 exact copies. It is important in puberty and other times of growth as it is the reproducing of your cells.

primase

An enzyme that joins RNA nucleotides to make the primer using the parental DNA strand as a template.

helicase

An enzyme that untwists the double helix of DNA at the replication forks.

DNA polymerase III

synthesizes new DNA only in the 5' to 3' direction; adds on the 3' side

DNA polymerase I

Removes RNA nucleotides of primer from 5' end and replaces them with DNA nucleotides; adding nucleotides on the 3' end

topoisomerase

corrects "overwinding" ahead of replication forks by breaking

ligase

An enzyme that connects two fragments of DNA to make a single fragment

Okazaki fragments

Small fragments of DNA produced on the lagging strand during DNA replication

leading strand

The new continuous complementary DNA strand synthesized along the template strand in the mandatory 5' to 3' direction towards the replication fork

lagging strand

A discontinuously synthesized DNA strand that elongates by means of Okazaki fragments

telomeres

Repeated DNA sequences at the ends of eukaryotic chromosomes.

telomerase

An enzyme that catalyzes the lengthening of telomeres.

PCR

(polymerase chain reaction) a method used to rapidly make multiple copies of a specific segment of DNA; can be used to make millions of copies of DNA from a very small amount of DNA

5' end of DNA

phosphate group on the C5 carbon of the sugar

3' end of DNA

refers to the end that has a hydroxyl group attached to the number 3 carbon of deoxyribose sugar

semi-conservative replication

in each new DNA double helix

purines

Bases with a double-ring structure.

Adenine and Guanine

pyrimidines

bases with a single ring structure

nucleotide

A building block of DNA

Polymerases add nucleotides on the

3' end of the strand being built

prokaryotic cell genetic material

DNA is a single molecule

eukaryotic cell genetic material

DNA is bound in a nucleus- DNA can also be found in some organelles such as mitochondria and chloroplasts