DNA and RNA Structure and Function

Vocabulary flashcards covering key concepts from the lecture on DNA and RNA structure and function.

DNA

Deoxyribonucleic acid, the molecule that carries the genetic instructions for life.

RNA

Ribonucleic acid, a molecule involved in protein synthesis and gene expression.

Nucleotide

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

Base pairing

The specific pairing of nitrogenous bases in DNA: adenine pairs with thymine (A-T) and guanine pairs with cytosine (G-C). In RNA, uracil replaces thymine.

Transcription

The process where DNA is used as a template to synthesize RNA.

Translation

The process of converting the sequence of a messenger RNA (mRNA) into a sequence of amino acids in a protein.

Operon

A cluster of genes under the control of a single promoter and operator, commonly found in prokaryotes.

Gene expression

The process by which information from a gene is used to synthesize a functional gene product, usually a protein.

Semiconservative replication

A method of DNA replication in which each daughter molecule consists of one original strand and one new strand.

Introns

Noncoding sections of a gene that are transcribed into precursor mRNA but are removed during RNA processing.

Exons

Coding sections of a gene that are retained in the process of mRNA splicing.

Codon

A sequence of three nucleotides in mRNA that corresponds to a specific amino acid.

Anticodon

A sequence of three nucleotides in a tRNA that is complementary to a specific codon in mRNA.

DNA polymerase

An enzyme responsible for synthesizing new strands of DNA during replication.

RNA polymerase

An enzyme that synthesizes RNA from a DNA template during transcription.

Helicase

An enzyme that unwinds and separates the two strands of DNA during replication.

Ribosome

A cellular structure that facilitates the synthesis of proteins by bringing together mRNA and tRNA.

Chromatin

A complex of DNA and proteins in the nucleus that condenses to form chromosomes during cell division.

Heterochromatin

Tightly packed form of DNA, which is transcriptionally inactive.

Euchromatin

Less condensed form of chromatin that is actively involved in transcription.

Alternative splicing

A process that allows a single gene to code for multiple proteins by varying which exons are included in the final mRNA.