welcome to the lab!! lab safety - it’s mostly common sense… think about what you are doing...
TRANSCRIPT
LAB SAFETY - it’s mostly common sense… THINK ABOUT WHAT YOU ARE
DOING BEFORE YOU DO IT!! THINK ABOUT WHAT THE
CONSEQUENCES COULD BE!! LISTEN TO ANY SPECIAL
INSTRUCTIONS!! Go over safety/disposal stuff
Microworlds Project You are required to complete 14
Microworlds entries (7 pages) – approx 1 pg / week.
Form will be available on my lab site Samples today that you may use for
microworlds include: human cheek cells and bacteria slides.
Always carry with 2 hands Only use lens paper for cleaning Do not force knobs Keep scopes away from edges of tables Watch out for cords!! Put away as listed on
cabinet door.
Eyepiece
BodyTube
RevolvingNosepieceArm
ObjectiveLens
StageStageClips
CoarseFocus
FineFocus
Base
Diaphragm
Light
Animation: Starr Ch 4How a Microscope Works
(JV, walk students thru microscope) Put the stage all the way DOWN Place the Slide on the Microscope Rotate to the lowest (shortest)
objective power (it should be stored this way)
Look into the Eyepiece Use the Coarse Focus
Start focusing using lowest power! Switch to the next higher objective Do NOTuse the Coarse Focus Knob Use ONLY the Fine Focus Knob to
bring the slide into focus!
Focus on low power (4X), focus on 10X, focus on 40X
If using 100x, move to half-way between 40X and 100X (oil immersion)
Add a very small amount of oil (less than 1 drop)
Click 100X into place Do NOT move back to 40X, you’ll get oil on it!
Move the 100X lens to front. CLEAN lens with lens paper. CLEAN lens only w/ lens cleaner solution &
lens paper! Kimwipes are not lens paper CLEAN slide with Kimwipe or papertowel NEVER use coarse focus with this lens!!
Oil has a similar refractive index as glass
Keeps light rays from bending going through sample
Increases resolution
Lab 1
1. You will be working thru the lab & recording your observations on p 16.
2. Parts & use of a microscope (quickly)
3. Examining an “e”
4. Depth of focus
Estimating Organism Size How would you
determine the actual size of this organism?
Be quick and dirty, it is longer than wide
Observing Cells Staining Human Cheek Cells
Add stain before adding coverslip or Stain cell by adding stain and “pulling”
under cover slip with a paper towel Disposal: Put slide and cover slip in
bleach
Warnings! Avoid long black “organisms” that move when
you blink (your eyelash) Avoid very slow-moving circular “cells” with
thick black borders Do not force the microscope You can only use coarse focus on low power! CLEAN off oil immersion lens AND slide when
you’re finished with lens cleaner and lens paper