Bioimaging and microscopy

Bouin's fixative contains this compound in addition to formaldehyde and acetic acid Perserves excellent nuclear structuresIs explosive in its dry form

Picric Acid

Penetrates well and precipitates proteins Can unfortunately leave metal precipitates in the tissueUnsuitable of frozen sections

Mercury based fixatives

One of the oldest fixatives Fixes nuclear but not cytoplasmic proteins Makes the tissue hard and causes swelling and is therefore used alone. Is a component of Bouin's fixative

Acetic acid

Slow and precipitating fixative Used e.g. for enzyme determination and on already sliced samples

Aceton

Mostly used in electronmicroscopy

Glutaraldehyde

Crosslinks proteins Used e.g. for immunostaining A variant beginning with "glutar" is well suited for electronmicroscopy

Aldehydes

Slicing frozen material embedded in OCT

Cryostat

Slicing paraffin embedded material

Microtome

Slicing unembedded and even unfixed material

Vibratome

correct order for processing samples for paraffin embedding

1) Fixing 2) Dehydration 3) Clearing 4) Paraffin embedding 5) Slicing 6)Rehydration 7) Staining 8) Dehydration+montering

Why is a sample fixed?

To prevent postmortem damage

Are used together with dyes. Makes the staining more intense.

Auxchromes

Alters the energy of the electron cloud of benzene, leading to absorbance of visible light.

Chromophores

Dyes that are solved in and stain fats.

Lysochromes

Metal salts that form multivalent metal ions in solution (Fe3+, Al3+). Forms chelates with the dye.

Mordants

Which staining method will you choose if you want to study transcription of genes (mRNA)

In situ hybridisation

Which staining method will you choose if you want to study tissue structures?

Histological staining

Which staining method will you choose if you want to study specific molecules?

Immunohistochemistry

Haematoxylin is primarily used for staining

the nucleus

The human naked eye can distinguish electromagnetic radiation within the interval:

400-700nm

What is it called when the tissue is over stained, after which it is destained until an optimal shade is achieved?

Regressive staining

Fluorescein isothiocyanat (FITC) and Rhodamin are examples of

Fluorophores

What part is the most decisive for the magnification and the resolution of a microscope?

Objective

What does "n" stand for in NA = n x sin v?

refractive index

What is the name of the part that regulates the numerical aperture of the condenser?

Aperture diaphragm

In which country were the first microscopes developed at the turn of the 16th and 17th century?

Netherland

A microscopy work shop that was founded in Jena in the 1800's was very important for the development of microscopes. The founder was a colleague of Ernst Abbe and August Köhler. What was his name?

Carl Zeiss

What is the name of the part of the microscope that is used for watching?

Occular (eyepiece)

One of the pioneers from the 17th century constructed more than 500 microscopes, which he used to detect bacteria and protists. He was self-taught and made most of his career in Delft. What was his name?

Anthony van Leeuwenhoek

What was the name of the italian that found capillaries and alveoli and that is regarded as the founder of microscopic anatomy?

Marcello Malpighi

What is the name of the part that guides the light beam aginst the sample

Condenser

What is the part that adjusts the size of the light field called?

Field diaphragm

What was the name of the scientist that wrote Micrographia in the 1600's and that described cork tissue as "cells"?

Robert Hooke

Ernst Abbe's impact on the development of microscope techniques was significant. Within which field of microscopy ?

Optical theories

What is it called when the lens does not refract all wavelengths (colours) the same way?

Chromatic aberration

What is it called when the image that a lens produces is spherical instead of planar?

Filed curvature

What is it called when the refraction of light varies depending on its distance from the middle?

Spherical aberration

After a fluorophore is excited it gives away light, which is called

Emission

What are substances that refract differently polarised light differently called?

Anisotropic

Oscillations/cycles per second=

Frequency

What is it called when light passes through a sample instead of being reflected or absorbed by it?

Transmission

What is the word for bending of a light beam?

refraction

When light passes from one transparent substance to another it will be refracted, unless the substances have the same... (This is not the case if the angle of incidence is 90° or very small.)

Refractive index

If a surface reflects light waves of certain visible wavelengths and absorbs light waves of certain other visible wavelengths, we see the surface having a certain...

Colour

What is it called when two light waves in the same phase interact?

Constructive interference

Give another name for the oscillation plane of light.

Polarisation

What does the unit lambda (λ) indicate?

Wavelength

Combine the correct components with the correct microscope: Normarski prism

Interference contrast microscopy

Combine the correct components with the correct microscope: Dark field condenser

Dark field microscopy

Combine the correct components with the correct microscope: Magnets instead of lenses

Electron microscopy

Combine the correct components with the correct microscope: Phase plate

Phase contrast microscopy

Combine the correct components with the correct microscope: Laser

Confocal microscopy

Combine the correct components with the correct microscope: The light passes an emission filter on the way to the eyepiece

Fluorescence microscopy

What type of microscopes will you use to study the tissue samples that you will take images of on the course?

Light microscope