Vinegar Eel LAB The vinegar eel -- turbatrix aceti: -harmless roundworm -live in acidic oceans and lakes -1 to 2 mm long -points at both ends -smooth, slender body is nearly transparent -is possible to see its internal organs -one of lowest animals to have digestive tract complete with mouth and anus -multi-cellular, large enough to be seen with the naked eye

Vinegar Eel LAB -eels have muscles the whole length of their body and move through the vinegar with powerful whip like motions -females are larger than males -females give live birth—about 45 every 8-10 days -life cycle of a vinegar eel is about 10 months

Vinegar Eel LAB -The eel spends its entire life in unpasteurized vinegar, a very acid environment. -We use pasteurized vinegar at home, so we do not see vinegar eels in our vinegar. -Pasteurization is a process of heating the liquid to a high temperature to destroy microbes. -It produces sterilized vinegar, which completely eliminates the possibility of our finding these eels on our kitchen shelf.

COMPLETE PRE-LAB COMPLETE pre-lab requirements READ through LAB requirements FIRST!! Use your lab write-up handout as a resource. IDENTIFY: 1-factor/material to be tested 2-Question

COMPLETE PRE-LAB 1-PRE-LAB PROCEDURES -SCIENTIFIC METHOD components 2-PRE-LAB PROCEDURES -COMPLETE procedures prior to LAB class period -procedures should FLOW from one step to the next -include important details -instructor should be able to perform lab based on information in the PROCEDURES

PRE-LAB REVIEW LAB GROUPS: (5 min) PROBLEM/QUESTION: Does the ________ affect the ________? HYPOTHESIS: If the ________ then the _________ IV- ___________________ DV- ________________________ IV DV IV DV Pollutants vinegar eel’s response LAB GROUPS: (5 min) COMPARE PRE-LAB information for group concesus PEER REVIEW PRE-LAB PROCEDURES

PRE-LAB REVIEW CONSTANTS: EXPERIMENTAL GROUP: CONTROL GROUP: amount pollutant, amount vinegar eel suspension, same eel population, time observed, microscope/power, … Eels w/pollutants A & B added Eels w/NO pollutant added

COMPLETE PRE-LAB 3-MATERIALS -vinegar eels -microscope -well slides / spot plates -droppers -

GATHER MIMATERIALS MICROSCOPE ----------------------------------- -Turn the ocular lenses to LOW power (short lens) -Raise the stage to its highest position -Adjust the eyepiece so you can easily see -PLUG IN / TURN ON MICROSCOPE

Collecting the vinegar eel Preparing a control AT THE CART-- 1-DRAW up small amount of vinegar from the jar with eels 2-Place 2 drops of vinegar eel solution into the center of well 3-RETURN any vinegar left in the dropper to the vinegar eel jar Gently drop it close to the surface of the water RETURN TO LAB STATION-- 4-OBSERVE the normal movement of eels under the microscope *LOW POWER ONLY -pay attention to vigor of wriggling and organism’s progress as it moves forward

Observing hints vinegar eels -LOOK for eels at the edge of the sample [eels do not like the light] -Once you have found eels moving, focus in and move the slide/plate to locate moving eels TIP: Try blocking some of the light with your hand

EEL DRAWING - LAB -DRAW and DESCRIBE (qualitative) -Include comments on size and movement -DETAILED drawings, include ENTIRE VIEWING AREA

PRACTICE TIMING: vinegar eel -Using dropper provided at the front cart, carefully draw up a very small amount of CLEANER from the jar -Place 2 drops of CLEANER in the center of WELL with eels -OBSERVE EEL movement over several minutes— do the EELS speed up or slow down -RECORD time for EEL to COIL (if they coil)

Slowing Down Vinegar Eels 1-Place a few grains of undissolved, unflavored gelatin in SLIDE - B WELL -As the gelatin absorbs liquid and expands, it slows the vinegar eels considerably. -OBSERVE EEL movement over several minutes— do the EELS speed up or slow down -RECORD time for EEL to COIL (if they coil)

CLEAN-UP 1-Rinse off slide in sink with clean water -place upside down on paper towel for drying -do NOT rub with paper towels 2-turn off and replace microscope (back of station) -wind up cord!! 3- WIPE down lab station