?Vinegar Eel LAB

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?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

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?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 birthabout 45 every 8-10 days
• -life cycle of a vinegar eel is about 10 months

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?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.

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?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
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?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

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?PRE-LAB REVIEW

• PROBLEM/QUESTION
• Does the ________ affect the ________?
• HYPOTHESIS
• If the ________ then the _________
• IV- ___________________
• DV- ________________________

DV
IV
IV
DV
Pollutants
vinegar eels response
LAB GROUPS (5 min) COMPARE PRE-LAB information
for group concesus PEER REVIEW PRE-LAB PROCEDURES
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?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
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?COMPLETE PRE-LAB

• 3-MATERIALS
• -vinegar eels
• -microscope
• -well slides / spot plates
• -droppers
• -

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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
• -----------------------------------

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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
  organisms progress as it moves forward

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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

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EEL DRAWING - LAB

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

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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)

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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)

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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