2. Uses of Light Flashcards
How (3) can we see parts of cells?
- Cut tissue into thin slices.
- Remove individual cells.
- Label.
How do you cryosection a tissue?
- Freeze tissue in medium.
- Cut into slices.
- Keep forzen till needed.
Give an advantage of fluorescense?
Multiple color labels.
Outline how BRIGHT FIELD microscopy works?
- Colored dyes stain samples.
- Allowing different wavelengths to be absorbed.
- Light travels from bottom to top.
How does a BRIGHT FIELD sample typically appear?
Dark sample on white background.
What colour does Haemotoxylin stain tissues?
Basic substances turn blue such as DNA.
What colour does Eosin stain tissues?
Acidic substances stain pink such as protein.
Outline how PHASE CONTRAST microscopy works?
- Sample is stained.
- Light travels from top to bottom.
- Phase contrast makes transparent cells visible.
What kind of cells does PHASE CONTRAST microscopy image?
Live cells.
What kind of imaging process does PHASE CONTRAST microscopy use?
Absorbance
What are the (4) imaging processes?
- Florescence.
- Luminescence.
- Absorbance.
- Reflectance.
What is a FLUOROPHORE?
Compound that emits light (photon) after excitation.
How does fluorescence appear?
- glows against a black background.
How does fluorescence work?
Fluorophores absorb certain light wavelength but emits another.
What does LUMINESCENCE mean?
Emission of light by a substance that has not been heated.
