Module 14: Techniques in Cell and Molecular Biology

Flashcards covering key vocabulary terms related to microscopy, cell culture, protein and nucleic acid fractionation, recombinant DNA technology, and PCR.

Bright-Field Light Microscopy

A microscopy technique that produces a bright background with a contrasting specimen. It can be used to observe whole mounts or sections of cells.

Phase Contrast Microscopy

A microscopy technique that enhances the visibility of highly transparent objects by converting differences in the refractive index into light-intensity differences.

Differential Interference Contrast (DIC) Optics

A microscopy technique that gives a three-dimensional quality to the image.

Fluorescence Microscopy

A microscopy technique utilizing fluorophores that release visible light upon absorption of UV rays, used for live-cell imaging and to follow genes of interest using variants of GFP.

Immunofluorescence

A technique where a small organic fluorophore is covalently linked to an antibody to produce a fluorescent antibody, used to locate specific cellular structures.

Primary Culture

Cells obtained directly from an organism for cell culture.

Secondary Culture

Cells derived from a previous cell culture.

Cell Line

Cells with genetic modifications that allow them to grow indefinitely in culture.

Two-Dimensional Culture System

Cells grown on the flat surface of a dish.

Three-Dimensional Culture System

Cells grown in a 3D matrix consisting of extracellular materials to better study cell-cell interactions.

Differential Centrifugation

A process that allows the isolation of organelles in bulk quantity through sequential centrifugations in density gradients.

Chromatography

A technique in which a mixture of dissolved components is fractionated as it moves through some type of porous matrix.

Ion Exchange Chromatography

A method to separate molecules based on the net charge of the protein using ion-exchange resins like DEAE-cellulose or carboxymethyl (CM) cellulose.

Gel Filtration Chromatography

A method to separate proteins by molecular weight using a column packed with cross-linked polysaccharides of different porosity.

Affinity Chromatography

A method that separates one protein from a mixture using a specific ligand, achieving near-total purification in a single step.

Polyacrylamide Gel Electrophoresis

A technique based on the migration of proteins in an electric field through a gel matrix, used to characterize proteins by molecular size, shape, and charge density.

Recombinant DNA

Molecules that contain DNA sequences derived from more than one source.

Restriction Endonucleases

Enzymes that function in bacteria to specifically cut viral DNA at palindromic sequences, used to dissect genomes into defined fragments.

DNA Cloning

A technique to produce large quantities of a specific DNA segment by inserting it into a vector DNA (e.g., bacterial plasmids or viruses) and replicating it within a host cell.

PCR (Polymerase Chain Reaction)

A method for specific DNA amplification that utilizes a heat-stable DNA polymerase (Taq polymerase), primers, and repeated temperature cycles to amplify DNA fragments.

Live-Cell Imaging

A microscopy technique that enables the observation of live cells over time, allowing researchers to study dynamic biological processes.

Cell Differentiation

The process by which a less specialized cell becomes a more specialized cell type, often involving changes in gene expression.

Apoptosis

A form of programmed cell death that occurs in multicellular organisms, characterized by specific cellular changes and eventual death.

Cell Proliferation

The process by which cells divide and reproduce, leading to growth and development of tissues.

Transfection

The process of deliberately introducing nucleic acids into cells, allowing for the study of gene function and expression.

Gene Editing

The alteration of a specific DNA sequence within the genome of an organism, commonly performed using technologies like CRISPR-Cas9.

Flow Cytometry

A technique used to analyze the physical and chemical characteristics of cells or particles, allowing for rapid quantification and sorting.

Cell Signaling

The communication process that governs basic cellular activities and coordinates cell actions, often involving signal transduction pathways