Unit 2: Lab Skills

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Unit 2 Lab Skills
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Tools for Measurement

• Metric Ruler
• Measures length
• Units
• cm, mm, or Mm (micrometers)
• 0.1 cm 1.0 mm 1,000.0 Mm
• (Inches are NOT allowed !!)
• Convert the following
• 32.0 cm ________ ____________Mm

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Measuring Length- under the microscope
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Graduated Cylinder

• Measures Volume_______________________
  
• Units ml (milliliters)
• Whats the volume of water in the cylinder?
  _______

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Thermometer

• Measures Temperature
• Units
• Degrees Celsius (oC)
• Temps to Remember
• Boiling pt of Water ______
• Body Temperature ______
• Freezing pt of water ______

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Measuring Mass

• Mass ____________________________
• Units
• grams
• Electronic Balance
• Triple Beam Balance

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Microscope Skills

• A microscope is an instrument that uses lenses to
  make an object easier to see in detail. It
  magnifies objects.
• There are 2 types of Microscopes
• 1. Stereoscope (aka- dissecting microscope)
• 2. Compound Light Microscope

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Stereoscope

• (2) ocular eyepiece lenses
• (1) objective lens
• Lower magnification
• 3-D image that is NOT reversed
• Used to look at insects, worms, flowers, etc.

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Compound Light Microscope

• Requires a light source
• 1 or 2 ocular eyepiece lenses
• Usually a 4X, 10X, and sometimes a 40X objective
  lens
• High magnification but in REVERSE
• Used to view very small objects

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Parts of a Microscope
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Microscope Parts and their functions

• Using the handouts from class
• Be sure that you are able to identify each
  of the parts of the microscope and describe its
  function.
• Remember Microscopes are used for
• focusing and sometimes staining specimens
• Refer to Textbook pp 947-948 in the
  classroom

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Additional Lab Techniques

• I. Electrophoresis a very powerful tool that
  allows scientists to separate mixtures of large
  molecules according to size
• DNA and Proteins are very large molecules
• 2 Types
• 1. Protein Gel Electrophoresis
• 2. DNA Gel Electrophoresis

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Whats Protein Whats DNA??

• Protein- makes up enzymes and many cell parts
• DNA- carries heredity information

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Protein Gel Electrophoresis
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What is the purpose of DNA Electrophoresis?

• The results of this technique provides you with a
  Bar Code pattern that is used to determine
• Whos your Daddy?
• Who Dunnit?
• Which animal group is being killed by
  poachersis it the same family??
• Genes for specific genetic diseases

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Electrophoresis Virtual Lab

• Lets go to the Computer Lab
• Go to the following address to perform the lab
  Have Fun!!
• Click on the bell
• http//learn.genetics.utah.edu/content/labs/gel

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More Lab Techniques
II. Chromatography While chlorophyll is the
chief pigment responsible for photosynthesis in
green plants, many plants contain other colored
pigments as well. These chlorophyll and colored
pigments may be separated according to their
various chemical charges by a technique known as
chromatography. In this technique, a mixture of
plant pigments is separated by placing a drop or
two of pigment on a special paper called
chromatography paper which is dipped in a
chemical allowing the different plant pigments to
move based on their charges. A picture of a
completed chromatography may be viewed in the
graphic at the right.
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III. Stains Indicators

• Stains make cell parts more visible
• Iodine (lugols solution)-darkens structures
• Methylene Blue -stains nucleus parts well!
• Indicators substances that change color
  when it contacts certain chemicals
• pH paper 7-14base
• 7 neutral
• 0-7 acid
• Iodine changes from golden brown to blue-black
  in the presence of starch

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A stained slide of a mud puppies intestine

• A mud puppy is a large salamander.

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IV. Dichotomous Keys

• These are used to sort, name, /or classify
  organisms.

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Observing Plant Animal Specimens

• Dissection the examination of preserved
  specimens...
• It requires
• Knowledge of equipment and how to use it
• A clean work area

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Lab Safety (text p.946)

• 1.
• 2.
• 3.
• 4.
• 5.

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Lab Safety

• 6.
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• 8.
• 9.
• 10.