Unit 2: Foundations of Molecular Genetics Study Guide

Vocabulary flashcards covering protein synthesis, prokaryotic and eukaryotic gene regulation, operons, viral structure, protein functional classes, amino acid anatomy, and cell models in biotechnology from the Unit 2 Molecular Genetics review.

Transcription

The process occurring in the nucleus where DNA is used to synthesize messenger RNA ($\text{DNA} \rightarrow \text{mRNA}$).

Translation

The process occurring at the ribosome where messenger RNA is decoded to synthesize a polypeptide or protein ($\text{mRNA} \rightarrow \text{protein}$).

R-plasmid

A specific type of bacterial plasmid that contains an antibiotic resistance gene.

Transformation

The process of using a plasmid as a vector to insert a foreign gene into a new host organism.

Operon

A genetic unit consisting of a piece of plasmid coding a gene where RNA polymerase binds to a promoter to direct gene expression.

Lac Repressor

A regulatory protein that binds tightly to the operator when lactose is absent, physically blocking RNA polymerase and preventing transcription of the operon.

Allolactose

A rearranged form of lactose that binds to the lac repressor, causing it to release from the operator so RNA polymerase can transcribe the operon.

Enhancers

Eukaryotic DNA sequences that increase gene expression and protein production when bound by activator transcription factors.

Silencers

Eukaryotic DNA sequences that decrease or inhibit gene expression when bound by repressor transcription factors.

Transcription Factors

Regulatory proteins that bind to specific DNA sequences to influence and regulate gene expression; a major focus of biotechnology research for mass-producing or inhibiting proteins.

Exons

Coding regions of eukaryotic RNA transcripts that are spliced together to form the final mature mRNA translated into protein.

Introns

Noncoding regions of eukaryotic RNA transcripts that are excised and removed during RNA processing.

Viruses

Biological entities composed strictly of a protein coat surrounding genetic material, typically named after the host organism they infect.

R group

The distinct side chain attached to the central carbon of an amino acid that varies in structure and makes each amino acid unique.

Structural Proteins

A functional category of proteins that provide architectural support to cells and tissues; examples include collagen, keratin, and tubulin.

Enzymes

Catalytic proteins typically indicated by the suffix '-ase' that accelerate biochemical reactions; examples include amylase and sucrase.

Transport Proteins

Proteins that facilitate the movement of ions or molecules across membranes or throughout an organism; examples include aquaporins, cytochrome c, and carrier proteins.

Contractile Proteins

Proteins that mediate mechanical movement and cellular contraction, primarily myosin and actin.

Hormone Proteins

Protein-based chemical messengers that coordinate bodily functions; examples include insulin and follicle stimulating hormone (FSH).

Antibody

An immune defense protein that identifies and neutralizes pathogens; an example provided is immunoglobulin A.

Pigment Proteins

Proteins that provide coloration or bind specific molecules via colored groups; examples include melanin and hemoglobin.

Recognition Proteins

Surface proteins such as glycoproteins that serve as cellular markers for identification and communication.

Toxins

Poisonous protein products produced by certain bacteria or organisms; examples include tetanus and diphtheria.

Cell Types for Protein Study

Host organisms and cell lines utilized in biotechnology to investigate, express, and mass produce proteins; examples include Plasmids, CHO cells, HeLa cells, Vera cells, and E. coli.