More microscopy - 2.3 (4) Flashcards
Module 2, Chapter 2, 2.3, Page 22
What can light emitted from other parts of the specimen do?
it would reduce the resolution and cause blurring
What happens to this unwanted radiation?
it does not pass through the pinhole and is not detected
What is used instead of light to get higher intensities?
a laser
What does a laser improve?
the illumination
How can very high resolution images be obtained?
through very thin sections of the specimen being examined and light from elsewhere being removed
What is moved across the specimen?
the spot illuminating the specimen
What is produced after the spot illuminating the specimen moved?
a two dimensional image is produced
How can a three dimensional image be produced?
by creating images at different focal planes
What is non-invasive?
laser scanning confocal microscopy
What is laser scanning confocal microscopy currently used in?
the diagnosis of diseases of the eye
What is laser scanning confocal microscopy also being used to develop the use for?
in endoscopic procedures
What can laser scanning confocal microscopes also be used in the development of?
new drugs
What does the future uses for advanced optical microscopy include?
virtual biopsies, particularly in cases of suspected skin cancer
What is the beam splitter?
a dichroic mirror which only reflects one wavelength (from the laser) but allows other wavelengths to pass through
What does the position of the two pinholes suggest?
the light waves from the laser follow the same path as the light waves radiated when the sample fluoresces
Both pinholes will have the same…
focal plane, hence the term confocal
By using antibodies with fluorescent tags, what can be targeted?
specific features
It can also be studied by confocal microscopy with much more…
precision than using staining and light microscopy
What is produced by the jelly fish Aequorea victoria?
Green fluorescent protein (GFP)
What does the GFP emit?
bright green light when illuminated by ultraviolet light
What have GFP molecules been engineered to do?
to fluoresce different colour
What can be studied at the same time due to GFP molecules being engineered to fluoresce different colours?
different components of a specimen
What has been isolated and can be attached to gene coding for proteins under investigations?
the gene for GFP
What does fluorescence indicate?
that a protein is being made and is used to see where it goes within the cell or organism
What has been modified to express this gene and fluoresce?
bacterial, fungal, plant, and, human cells
What does the use of these fluorescing proteins provide?
a non-invasive technique to study the production and distribution of proteins in cells and organisms
