Molecular Biology of the Gene

These flashcards cover key concepts and terminology from the lecture on molecular biology, specifically focusing on DNA, RNA, genetic information flow, and bacterial genetics.

DNA

The molecule that carries genetic information in living organisms.

RNA

A nucleic acid that is involved in protein synthesis and the transmission of genetic information.

Genotype

The genetic makeup of an organism, determining its traits.

Phenotype

The physical expression of the genotype; the observable traits of an organism.

Base Pairing

The specific pairing of nitrogenous bases in DNA; adenine pairs with thymine, and guanine pairs with cytosine.

Transcription

The process of synthesizing RNA from a DNA template.

Translation

The process of synthesizing a polypeptide from the RNA sequence.

Codon

A sequence of three nucleotides on mRNA that codes for a specific amino acid.

Mutation

A change in the DNA sequence that can affect the production of proteins.

Plasmid

A small, circular DNA molecule found in bacteria that can replicate independently of chromosomal DNA.

Bacteriophage

A virus that infects bacteria, often used in genetic studies.

Gene

A segment of DNA that codes for a protein or RNA molecule.

Nucleotide

The basic building block of DNA and RNA, consisting of a sugar, a phosphate group, and a nitrogenous base.

Hershey-Chase experiment

An experiment that demonstrated DNA is the genetic material of phages by showing that only the DNA entered the host cell.

Semiconservative replication

The method of DNA replication where each new DNA molecule consists of one original strand and one new strand.

Translation machinery

The combination of ribosomes, tRNA, and mRNA that synthesizes proteins.

Ribosome

A cellular structure that facilitates the translation of mRNA into polypeptides.

Introns and Exons

Introns are non-coding sequences removed during RNA processing, while exons are coding sequences that remain.

Reverse transcription

The process by which RNA is used as a template to synthesize DNA, characteristic of retroviruses like HIV.

Antigen

A protein on the surface of pathogens that triggers an immune response.

Transduction

The transfer of DNA from one bacterium to another by a bacteriophage.

Conjugation

The process where bacteria transfer genetic material through direct contact.

Transformation

The uptake of foreign DNA from the surrounding environment by a bacterial cell.