Molecular Biology of Genes and Genetic Expression

Deoxyribonucleic acid

DNA's full name, located in eukaryotic cell nuclei.

Messenger RNA (mRNA)

The RNA that carries information from DNA to the ribosome for protein synthesis.

F factor

A specific piece of DNA, often existing as a plasmid, that enables a donor E. coli cell to carry out conjugation.

Epigenetic inheritance

Resulting from chemical modification of DNA bases or histone proteins, influencing gene expression.

Promoter

A specific nucleotide sequence that acts as a binding site for RNA polymerase and determines where transcription starts.

RNA Splicing

The process of removing introns and reconnecting exons in a pre-mRNA.

Transfer RNA (tRNA)

RNA that helps decode a messenger RNA (mRNA) sequence into a protein.

Ribosome

A cellular structure that facilitates the joining of amino acids during protein synthesis.

Lytic Cycle

A viral replication cycle where the virus replicates and destroys the host cell.

Emerging Viruses

Viruses that appear suddenly and become apparent to the medical community.

Prions

Infectious proteins that can cause abnormal folding of normal cellular proteins.

Transformation

The uptake of DNA from the surrounding environment by bacteria.

Alternative RNA splicing

A process after transcription where multiple types of mRNA are generated from the same transcript, allowing for protein diversity.

Noncoding RNAs

RNA molecules that do not code for proteins but play roles in controlling gene expression.

Measles

Caused by a contagious virus with a red rash.

Frederick Griffith

Discovered bacterial transformation in 1928.

Hershey and Chase

Confirmed DNA as genetic material using phages.

Nucleotide

Consists of a base, sugar, and phosphate group.

Ribonucleic acid

RNA with uracil and ribose, unlike DNA.

Watson and Crick

Described DNA's double helix structure in 1953.

Semiconservative model

DNA replication with one old and one new strand.

DNA polymerase

Enzyme synthesizing daughter DNA strands.

Transcription

DNA to RNA synthesis.

Translation

RNA to protein synthesis.

Codons

Nonoverlapping three-base words in DNA and RNA.

Genetic code

Rules for translating mRNA triplets into amino acids.

Genetic Code

The set of rules by which information encoded in genetic material (DNA or RNA sequences) is translated into proteins.

Initiation Codon

The codon that signals the start of translation and the amino acid methionine.

Elongation

The stage in translation where amino acids are added to the polypeptide chain.

Stop Codon

A nucleotide triplet within messenger RNA that signals a termination of translation.

Mutation

A change in the nucleotide sequence of an organism's DNA.

Lysogenic Cycle

A viral replication cycle where the viral genome is integrated into the host cell's chromosome.

Retrovirus

A virus that carries its genetic material in the form of RNA and uses reverse transcriptase to make DNA from RNA.

Transduction

Gene transfer by phages in bacteria.

Conjugation

The transfer of DNA from a donor to a recipient bacterial cell in bacteria.

R plasmids

Plasmids that carry genes for enzymes destroying antibiotics, posing problems for human medicine.

Gene expression

The process by which genetic information flows from genes to proteins, regulating responses to environmental changes.

Operons

Units in prokaryotes where genes for related enzymes are controlled together.

Transcription factors

Proteins that promote the binding of RNA polymerase to a gene in eukaryotic transcription.