Genetic Material, Replication, Transcription, Translation, Mutations, Protein Folding and Trafficking

Flashcards covering key vocabulary terms related to genetics, replication, transcription, translation, mutations, protein folding, and protein trafficking.

Nucleotide

Building block of nucleic acids, composed of a phosphate group, sugar (deoxyribose in DNA, ribose in RNA), and a nitrogenous base (A, T, C, G in DNA; A, U, C, G in RNA).

Phosphodiester bond

The bond that links the sugar of one nucleotide to the phosphate of the next, forming polynucleotides.

Transformation (Griffith's experiment)

Process where heat-killed pathogenic bacteria transfer genetic information to non-pathogenic bacteria, making them pathogenic.

Bacteriophage

Virus that infects bacteria; used by Hershey and Chase to demonstrate DNA as genetic material.

Chargaff's Rules

Base composition regularities in DNA: %A = %T and %G = %C.

Semiconservative Model

DNA replication model where each daughter molecule has one parental strand and one new strand.

Origin of Replication (ORI)

Specific sequence where DNA replication begins.

DNA Polymerase

Enzyme that adds nucleotides to the 3' end of a preexisting chain during DNA replication.

Helicase

Enzyme that unwinds the DNA double helix.

Leading Strand

DNA strand synthesized continuously towards the replication fork.

Lagging Strand

DNA strand synthesized discontinuously away from the replication fork, forming Okazaki fragments.

Okazaki Fragments

Short fragments of DNA synthesized on the lagging strand.

DNA Ligase

Enzyme that joins Okazaki fragments on the lagging strand.

Replication Fork

Y-shaped region where the DNA double helix is unwound for replication.

RNA Polymerase

Enzyme responsible for reading the DNA template and synthesizing the RNA transcript.

Promoter

DNA sequence where RNA polymerase binds to start transcription.

Transcription Factors

Proteins that aid RNA polymerase binding and initiation of transcription.

Introns

Non-coding regions of a gene that are removed during RNA splicing.

Exons

Coding regions of a gene that are joined together to form the final mRNA.

Spliceosome

A complex of proteins and snRNAs that performs RNA splicing.

Codon

Nucleotide triplet in mRNA that specifies an amino acid or stop signal during translation.

tRNA (Transfer RNA)

RNA that brings amino acids to the ribosome and matches them with mRNA codons.

Wobble Pairing

Flexible base pairing at the third position of the codon, allowing fewer tRNAs to cover all codons.

Aminoacyl-tRNA Synthetase

Enzyme that attaches the correct amino acid to tRNA.

Ribosome

Composed of rRNA and proteins, facilitates tRNA and mRNA pairing, catalyzing peptide bond formation.

Mutation

Alteration in the DNA sequence.

Point Mutation

Mutation affecting one or a few nucleotides.

Silent Mutation

Mutation with no change in amino acid due to redundancy in the genetic code.

Missense Mutation

Mutation that changes one amino acid.

Nonsense Mutation

Mutation that creates a premature stop codon.

Frameshift Mutation

Mutation that alters the reading frame due to insertion or deletion of nucleotides.

Chaperone Proteins

Assist in proper protein folding and prevent aggregation.

Denaturation

Disruption of protein structure due to heat, pH, or chemicals.

Post-Translational Modification (PTM)

Modification that occurs to proteins after they have been synthesized by ribosomes.

Signal Peptide

Amino acid sequence that directs proteins to specific locations within the cell.

Ubiquitination

Attachment of ubiquitin, a small regulatory protein, to lysine residues on target proteins, tagging them for degradation by the proteasome.

Glycosylation

Attachment of carbohydrate groups to asparagine (N-linked) or serine/threonine (O-linked) residues on proteins.

Proteasome

protein complex that degrades and recycles damaged or misfolded proteins