Genetics Unit Test Review: The Molecular Basis of Life

Vocabulary flashcards covering DNA structure, historical experiments, and replication models based on the lecture notes.

DNA (Deoxyribonucleic Acid)

The carrier of genetic information within generations, used to instruct protein synthesis and ensure the continuity of life.

Genes

Coding DNA regions containing instructions for building proteins, which influence traits.

Frederick Meisher

The scientist who named "nuclein" after finding acidic phosphorus in white blood cells.

Hammerling

The scientist who determined that hereditary material likely resided in the nucleus.

Griffith

The scientist who discovered that a molecule from dead material could transform live bacteria and transfer hereditary information.

Avery, McCarty, Macleod

The team of scientists who identified DNA as the molecule that transforms bacteria.

Hershey & Chase

The scientists who confirmed DNA was hereditary material using bacteriophage.

Chargaff

The scientist who provided evidence of base-pairing in DNA.

Franklin

The scientist who generated X-ray diffraction data that suggested a helical structure.

Watson & Crick

The scientists who produced the double-helix model with inward-pointing H-bond bases, explaining Chargaff's data.

Deoxyribonucleotides

The monomers of DNA composed of a $5\text{C}$ sugar, a phosphate group, and a nitrogenous base ($A$, $G$, $C$, or $T$).

Antiparallel

The alignment of the two complementary strands in a double helix where the $3'$ (5-C Sugar) end aligns with the $5'$ (phosphate) end along a vertical axis.

DNA Sugar Composition

Unlike ribose sugar, the sugar in DNA lacks an oxygen on the $C-2$ position.

Purines

Double-ringed nitrogenous bases, specifically Adenine and Guanine.

Pyrimidines

Single-ringed nitrogenous bases, specifically Cytosine and Thymine.

DNA Dimensions

One complete turn of the helix is $3.4\text{nm}$ and the distance between each base pair is $0.34\text{nm}$.

A-T Bonding

The pairing between Adenine and Thymine, which involves $2$ H bonds.

C-G Bonding

The pairing between Cytosine and Guanine, which involves $3$ H bonds.

DNA Replication Timing

DNA replicates itself during the S-phase of Interphase, before cell division.

Conservative Model

A replication model where the parent DNA remains intact and synthesizes an entirely new/separate double helix.

Dispersive Model

A replication model where parent DNA is broken into fragments and both strands are synthesized in short, alternating sequences.

Semi-conservative Model

A replication model where two parent strands separate and each makes a copy of itself, resulting in daughter DNA with $1$ new and $1$ old strand.

Meselson & Stahl (1958)

Experiment that proved the semi-conservative model using heavy nitrogen ($^{15}\text{N}$), E. coli grown for $17$ generations, and light nitrogen ($^{14} ext{N}$$).