DNA Structure and Gene Function - Lecture Review

Vocabulary terms and definitions related to the structure and function of DNA, transcription, translation, and mutations.

Chargaff's Rules

Adenine (A) pairs with Thymine (T) and Guanine (G) pairs with Cytosine (C).

Double Helix

The structure of DNA; described as a twisted ladder with a sugar-phosphate backbone.

Nucleotide

The monomer subunit of DNA, composed of a phosphate group, sugar, and nitrogenous base.

Antiparallel Strands

Refers to the opposite orientation of the two strands of DNA, one running 5' to 3' and the other 3' to 5'.

Central Dogma of Molecular Biology

The process where DNA is transcribed to RNA, which is then translated to proteins.

Introns

Non-coding regions of an mRNA transcript that are removed before translation.

Exons

Coding regions of an mRNA transcript that are expressed after introns are removed.

RNA Polymerase

An enzyme that catalyzes the synthesis of RNA from a DNA template during transcription.

Translation

The process of synthesizing proteins from the mRNA sequence.

Codon

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

Mutation

A change in the DNA sequence that can lead to variations in gene function.

Transgenic Organism

An organism that contains a gene or genes which have been artificially inserted instead of the originally inherited DNA.

Recombinant DNA

DNA that has been formed artificially by combining constituents from different organisms.

Restriction Enzyme

An enzyme that cuts DNA at specific sequences, used in recombinant DNA techniques.

PCR (Polymerase Chain Reaction)

A technique used to amplify a specific DNA segment.

Transcription Factors

Proteins that bind to DNA and regulate transcription, playing a key role in gene expression.

Ribosome

A molecular machine that synthesizes proteins by translating mRNA into an amino acid sequence.

Genetic Code

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

Frameshift Mutation

A mutation caused by insertion or deletion of nucleotides, shifting the reading frame of the genetic message.

Lac Operon

A group of genes involved in the metabolism of lactose; regulated by the presence of glucose and lactose.