DNA Biology Flashcards

Flashcards for reviewing DNA Biology lecture notes.

Friedrich Miescher

Discovered nucleic acids and isolated a phosphate-rich chemical from the nucleus of cells, which he called Nuclein.

Gregor Mendel

Studied inheritance in peas and proposed the particulate theory of inheritance (genes).

Transformation (in the context of DNA)

A process in which external DNA is taken up by a cell and changes its morphology and physiology.

Fredrich Griffith

Conducted experiments with Streptococcus pneumoniae to study transformation.

R strain

Non-pathogenic strain of Streptococcus pneumoniae.

S strain

Pathogenic (disease-causing) strain of Streptococcus pneumoniae that has a capsule.

Oswald Avery, Colin McLeod, and Maclyn McCarty

Determined that DNA was the transforming principle.

Alfred Hershey and Martha Chase

Confirmed that DNA, not protein, is the genetic material using bacteriophages.

Bacteriophage T2

A virus that infects bacteria; used by Hershey and Chase in their experiment.

DNA

Deoxyribonucleic Acid, the genetic material.

RNA

Ribonucleic Acid.

Nucleotide

The monomer (subunit) of nucleic acids, composed of a phosphate, a five-carbon sugar, and a nitrogenous base.

Erwin Chargaff

Examined DNA from many species and established rules about the relative amounts of nucleotide bases.

Chargaff's Rules

The amount of A = T and the amount of G = C in each species.

Rosalind Franklin

Used X-ray crystallography to study DNA structure and produced a picture showing DNA to be a helix.

James Watson and Francis Crick

Developed the double helix model of DNA, explaining its structure and replication.

Double Helix

The structure of DNA, resembling a twisted ladder.

Complementary Base Pairing in DNA

A & T and G & C.

DNA Replication

The process of copying DNA during interphase of the cell cycle.

Semiconservative Replication

Each new DNA molecule consists of one parent strand and one new strand.

Helicase

Unwinds DNA during replication.

DNA Polymerase

Enzymes that joins the DNA nucleotides.

DNA Ligase

Seals breaks in the sugar-phosphate backbone of DNA.

Origins of replication

DNA replication begins at numerous of these in eukaryotes.