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Evolution Study Kits
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Ecology and Evolution— Evolution Study Kits, continued
Studying Seed Evolution Using Histograms—
Student Laboratory Kit
Looking for a creative way to teach evolution? Study seed evolution by making histograms! Evolution often conjures mental images of monkeys to cavemen to modern humans. In reality, evolution can be studied on a much simpler scale. Measure mass and length of sunflower seeds to see how such traits are selected in nature. Histograms created from the data allow students to analyze the frequency and symmetry of distribution and draw conclusions about the natural selection of seed size.
Complete for 30 students working in pairs. Five calipers are included for sharing among student groups. Additional calipers are available separately.
Spontaneous Generation—
Demonstration Kit
By: The Flinn Staff
Prior to Louis Pasteur, there was a commonly held belief that living microbes could arise from nonliving matter by a “mysterious” process known as spontaneous generation. Pasteur was ingenious in designing “controls” into experiments, and his classic S-tube flasks proved to be the key to dispelling the belief in spontaneous generation. You and your students can now easily duplicate Pasteur’s classic experiment with this convenient kit. In this demonstration, a series of media-filled flasks with different openings and treatments are exposed to air containing microbes. The only flasks that become contaminated are those where microbes can come in direct contact with the media. The S-shape flasks remain sterile even though they are open to the air. Why? Because microbes can’t “navigate” around the S-shaped bend in the glass. Set up in 1864, Pasteur’s open-air, S-shaped flasks are still sterile in a museum in France. Consider keeping the S-shaped flasks in your laboratory. They will remain sterile for years to come. Your students will be very impressed! Enough materials are provided for one complete demon- stration setup. Includes the pre-shaped S-tube, chemicals and complete teaching instructions.
Concepts: Sterilization, spontaneous generation.
Time Required: 25 minutes
Materials Provided: Nutrient broth, paraffin wax, rubber stoppers, straight and bent glass tubes.
Coacervate—Student Laboratory Kit
By: The Flinn Staff
Students actually produce the possible precursors
of life—coacervates. The liquid, colloidal suspension produced by students will exhibit some of the same properties of living organisms. When the membrane-like structures surrounding the droplets are stained, the coacervates look even more life-like.
Complete for 30 students working individually or in teams. Requires a compound microscope and slides.
ECOLOGY AND EVOLUTION— EVOLUTION STUDY KITS continued on next page.
Studying Seed Evolution Using Histograms—Student Laboratory Kit FB2011
Catalog No.
Description
Price/Each
FB2011
Studying Seed Evolution Using Histograms— Student Laboratory Kit
$52.30
AB1006
Vernier Calipers, Steel
10.35
Spontaneous Generation—Demonstration Kit FB1437
Catalog No.
Description
Price/Each
FB1437
Spontaneous Generation—Demonstration Kit
$37.75
Catalog No.
Description
Price/Each
FB1430
Coacervate—Student Laboratory Kit
$28.65
Coacervate—Student Laboratory Kit FB1430