WELCOME TO THE LAB!!

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

Measuring Field of View

Measuring Field of View

Estimating Organism Size How would you

determine the actual size of this organism?

Be quick and dirty, it is longer than wide

Estimating Organism Size How would you

determine the actual size of this organism?

MATERIALS: Clean slide Square coverslip Sample 1-2 drops of water

Add sample and 1-2 drops of water

Lower a coverslip onto the slide starting at a 45 angle

e

Completed wet-mount slide should have no bubbles

e

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

OBSERVATIONS DRAW WHAT YOU

ACTUALLY SEE, not what you think it looks like.

Make it actual size

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

What you’re responsible for

I AM giving a quiz on the lab next week Questions from the quiz will be pulled

from the lab and the study guide questions at the end – DO THEM!