Summary: confocal microscopy is used for imaging fluorescent signals, usually in fixed specimens. It generates high resolution optical sections.

A Laser scanning confocal microscopy (LSCM) C. elegans image

This is a C. elegans embryoG at the 2-cell stage (bigger AB cell at bottom, P1 at the top). Red represents the membraneG, green represents the microtubules (MTs)G and blue shows its chromosomeG. This image combines images from 3 different channels. The membrane, MTs and chromosome were imaged using 3 channels, color-mapped to 3 colors (red, green, and blue).

bioclips: advantages of LSCM compared to widefield fluorescence microscopy

By applying pinhole apertureG to LSCM

(Eliminate out-of-focus flare, 90 KB, movie length: 52")

(The thickness of optical section is controllable, 160 KB, movie length: 15")


1. LSCM image: Maria Vidal, the John White Lab at UW-Madison

2. Images in "Eliminate out-of-flare" flash movie: Haining Zhang, the John White Lab at UW-Madison

3. Images & movies in "The thickness of section is controllable" flash movie: Jayne Squirrell, the John White Lab at UW-Madison


Chromosome: in eukaryotes, the structural unit of the genetic material consisting of a single, linear double-stranded DNA molecule and associated proteins wrapped into a high order structure. During mitosis, chromosomes condense into compact structures visible in the light microscope. In prokaryotes, a single circular double-stranded DNA molecule constitutes the bulk of the genetic material.

Embryo: the early developmental stage of an organism (C. elegans in this case) after fertilization and before hatching.

Membrane: permeability barrier surrounding cells or organelles and consists of a phospholipids bilayer, together with associated membrane proteins.

Microtubule:long, cylindrical polymer composed of the protein tubulin. It is one of the three major classes of filaments in the cytoskeleton.

Pinhole Aperture: a device used in confocal microscopy to control the amount of light admitted to the detector. This allows for a clearer image by preventing out of focus light from reaching the detector.