Key Concepts in DNA and RNA Function

DNA

Deoxyribonucleic acid, the molecule that carries genetic information in cells.

RNA

Ribonucleic acid, involved in protein synthesis and gene regulation.

Sugar phosphate backbone

The repeating structure of sugar and phosphate groups that form the backbone of DNA and RNA strands.

Histones

Proteins that DNA wraps around to form nucleosomes, aiding in chromosomal structure.

Double helix

The twisted ladder shape of DNA, with two strands wound around each other.

DNA polymerase

An enzyme that synthesizes new DNA strands during replication.

Origin of replication

The starting point where DNA replication begins.

Replication fork

The Y-shaped region where the DNA is split into two strands for replication.

Replisome

A complex of enzymes and proteins that coordinate DNA replication.

Template strand

The DNA strand used as a template for RNA synthesis.

Non-template strand

The DNA strand not used as a template during transcription.

Anti-codon

A sequence of three bases in tRNA complementary to a codon in mRNA.

RNA polymerase

An enzyme that synthesizes RNA from a DNA template.

Transcription

The process of copying a DNA sequence into RNA.

Translation

The process of synthesizing a protein from an mRNA template.

Genetic code

The set of rules by which information in genetic material is translated into proteins.

tRNA

Transfer RNA, which brings amino acids to the ribosome during protein synthesis.

rRNA

Ribosomal RNA, a component of ribosomes that aids in protein synthesis.

mRNA

Messenger RNA, which carries genetic information from DNA to the ribosome.

Mutation

A change in the DNA sequence.

Ligase

An enzyme that joins DNA fragments together.

Helicase

An enzyme that unwinds the DNA double helix.

Primase

An enzyme that synthesizes RNA primers for DNA replication.

Okazaki fragment

Short DNA fragments formed on the lagging strand during replication.

Splicing

The process of removing introns from pre-mRNA to form mature mRNA.

Ribosome

A cellular structure that synthesizes proteins by translating mRNA.

Codon

A sequence of three nucleotides in mRNA that codes for an amino acid.

DNA Pol I

DNA polymerase I, involved in DNA repair and Okazaki fragment processing.

DNA Pol II

DNA polymerase II, involved in DNA repair.

DNA Pol III

DNA polymerase III, the main enzyme for DNA replication.

Exons

Coding regions of a gene that are expressed.

Introns

Non-coding regions of a gene that are spliced out during RNA processing.

Promoter

A DNA sequence where RNA polymerase binds to initiate transcription.

Operon

A group of genes regulated together under a single promoter.

Transcription factors

Proteins that regulate gene expression by binding to DNA sequences.

Enhancer

A DNA sequence that increases the transcription of a gene.

Telomeres

The protective ends of chromosomes.

Telomerase

An enzyme that extends telomeres.

Topoisomerase

An enzyme that prevents DNA tangling during replication.

Lipid rafts

Microdomains in cell membranes rich in cholesterol and sphingolipids.

Sphingolipids

A class of lipids containing a sphingoid base, important in cell signaling.

Cell communication

The process by which cells communicate with each other.

Hormone

A signaling molecule released by glands to regulate bodily functions.

Ligand

A molecule that binds to a specific receptor.

Kinase

An enzyme that adds phosphate groups to other molecules.