RNA and Protein Synthesis Vocabulary Flashcards

Vocabulary practice flashcards covering key terms and concepts from Chapter 13 on RNA structure, transcription, translation, mutations, and gene regulation.

RNA (Ribonucleic Acid)

A nucleic acid consisting of a long chain of nucleotides that uses coded DNA instructions to direct the production of proteins.

Messenger RNA (mRNA)

The type of RNA molecule that carries copies of instructions for assembling amino acids into proteins from DNA in the nucleus to the cytoplasm.

Ribosomal RNA (rRNA)

The type of RNA that forms an integral part of both subunits of a ribosome.

Transfer RNA (tRNA)

The type of RNA molecule that transfers each amino acid to the ribosome as specified by the coded messages in mRNA.

Transcription

The process in which segments of DNA serve as templates to produce complementary RNA molecules.

RNA Polymerase

An enzyme that binds to DNA during transcription, separates the strands, and assembles complementary RNA nucleotides using one DNA strand as a template.

Promoter

A specific region of DNA with a distinct base sequence where RNA polymerase binds to begin making RNA.

Intron

A portion of a pre-mRNA molecule that is cut out and discarded while still inside the nucleus.

Exon

A remaining portion of pre-mRNA that is spliced back together to form the final functional mRNA molecule.

Polypeptide

A long chain of amino acids joined together that forms a protein.

Genetic Code

The chemical language composed of four RNA bases (adenine, cytosine, guanine, uracil) read three bases at a time.

Codon

A group of three consecutive nucleotide bases in messenger RNA that specifies a single amino acid to be added to a polypeptide chain.

Translation

The process of decoding an mRNA message into a protein chain, carried out by ribosomes in the cytoplasm.

Anticodon

A sequence of three unpaired nucleotide bases on a tRNA molecule that are complementary to an mRNA codon.

Central Dogma of Molecular Biology

The foundational concept that genetic information moves in sequence from DNA to RNA to protein.

Gene Expression

The regulated process by which a gene produces its product and the product carries out its function in living cells.

Mutation

A heritable change in genetic information resulting from a change in a DNA sequence.

Point Mutation

A gene mutation involving a change in one or a few nucleotides occurring at a single point in the DNA sequence.

Frameshift Mutation

A point mutation, such as an insertion or deletion, that shifts the reading frame of the genetic message.

Mutagen

A chemical or physical agent in the environment that can interact with DNA and cause mutations at high rates.

Polyploidy

A condition in which an organism has extra complete sets of chromosomes, such as triploid ($3N$) or tetraploid ($4N$).

Operon

A group of genes in prokaryotes that are regulated together and usually have related functions.

Operator

The regulatory DNA region in an operon where a repressor protein can bind to block RNA polymerase.

RNA Interference (RNAi)

A mechanism of gene silencing where microRNA (miRNA) complexes destroy complementary mRNA sequences to prevent translation.

Differentiation

The process in which cells become specialized in structure and function during development.

Homeotic Gene

A master control gene that regulates the development of organs and body structures in specific parts of an embryo.

Homeobox

A conserved 180-base DNA sequence found within homeotic genes that codes for transcription factors involved in cell differentiation.

Hox Gene

A group of homeobox genes located side-by-side in a cluster that determines the exact identity of body segments from head to tail.