microscopy Flashcards
it is defined as the use of a microscope to visually enlarge objects too small to be visualized with the naked eye so that their characteristics are readily observable.
microscopy
why do we use microscopy
visualize cells and tissues
identify abnormalities
diagnose medical conditions
study tissue changes
Optical instrument that augments the power of the eye to see small objects.
microscope (Johannes Faber)
micro - small
skope - to view
commonly used: COMPOUND
properties of microscope
good resolution
- measured by its ability to differentiate 2 lines or points in an object
good contrast
- stain bind to cells = contrast increase
- default: tissues are transparent
good magnification
- small objects seem larger
- eyepiece is 10X
the first vision aid invented
reading stone
- glass on paper
who started to invented microscope from multiple lens in a tube
robert hooke
- first observe a cork through a microscope
- observe cells or pores
who built a simple microscope
Anton van Leeuwenhoek
- Can examine organism up to 300x magnification
rules when using the microscope
Carry the microscope properly.
Always begin focusing on the 4X objective.
Use the coarse focus only with the 4X objective in place.
Use immersion oil only with the 100X objective (oil immersion lens) in place.
Use only ONE drop of oil.
Lower the stage and then remove the slide when you are done.
ALWAYS clean the microscope when you are done. Use a kimwipe or lens paper and the alcohol in the labeled jars.
Always place the 4X objective over the stage and be sure the stage is at its lowest positions before putting the microscope away.
Always turn off the light before putting the microscope away.
Always wrap the cord correctly before putting the microscope away.
Always return the microscope to the correct cabinet.
Always place the oculus towards the BACK of the cabinet.
troubleshooting the microscope
If the bulb doesn’t light check if there is power supply, the bulb is blown off or not, rheostat is turned on etc.
If a slide is put on stage and the image cannot be viewed, check if the slide was probably placed upside down, no oil immersion was put on the slide or wrong objective being used.
If black dots appear on the lenses they may be on the eyepiece or slide, so if they move when the eyepiece is rotated, this means the dust is on the eyepiece.
If the black dot moves when the slide moves, it is present on the slide.
proper handling of the microscope
Clean the lenses after use with lens cleansing tissue and lens cleaning aid
Always remove oil from the objectives, stage, condenser and diaphragm using lens cleaning tissue and cleaning aid
Prevent immersion oil contact with other objectives other than 100x.
Never touch the optical lenses with bare hands since this leaves finger marks that will cause confusion.
Rotate the nosepiece to ensure that the lowest magnification objective remains in position at the end of each day.
Always cover the microscope to keep it away from dust when not in use.
Difference of brightfield and darkfield microscopy
index card
main applications in phase contrast microscope
Observing live cell movement (motility)
In-vitro fertilization monitoring
Examining cell shapes and structures
Detecting bacterial components like endospores
Studying unstained microorganisms
what are the uses for fluorescence microscope
Genetics
chromosome analysis
studying gene mutations
