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  1. Biology Inquiry with Invertebrates Charlie Drewes Ecology, Evolution & Organismal Biology Iowa State University Ames, IA 50011

  2. “ I hear and I forget, I see and I remember, I do and I understand.”Confucius

  3. ►Guided inquiry“BIOLOGY in ACTION” ►Open-ended inquiry”Stuck-onArtemia” ►Independent Inquiry“Biological Smoke Detectors”

  4. ‘BIOLOGYinACTION’ 31 Interactive &ComputationalAnimations WEB-based and CD(non-proprietary)

  5. INTERDISCIPLINARY AREAS:Biology, Math, Physics TOPICS & FOCAL POINTS:Locomotion BiomechanicsCell Biology Animal Behavior Physiology DevelopmentInvertebrate Biology

  6. CURRICULAR UTILITY: adjuncts to hands-onlaboratoryinquiries with living organisms adjuncts to lecture / discussion (homework or student presentations) focal points for problem-based learning (computation & data analysis)

  7. RED = interactive animations with computations and control featuresBLACK = GIF animations with questions and links ► ► ► LINK to CONTENTS

  8. Lumbriculus variegatusCalifornia blackwormAnnelida (Oligochaetea)

  9. Hands-on Lab Investigations with Living Lumbriculus  Segment Regeneration(ABLE)(development; asexual reproduction) Circulatory Function(ABT)(blood flow, pulse rate) Locomotion& Movement (ABT) (swimming, crawling, reversal behavior)

  10. Animations of Lumbriculus blood vessel pulsations:Adjunct to lab inquiry of circulation in living worms Interactive format

  11. CirculatoryComputations 0 sec 1 sec pulse frequency (pulse waves /sec) 2 sec  pulse velocity (mm /sec) 3 sec blood volume (cc3 / time) 4 sec 5 sec

  12. TAIL TOUCH  Animation of helical swimming in Lumbriculus: A follow-up to student lab inquiry of locomotion in living worms

  13. Helical swimming in Lumbriculus: A unique form of animal locomotion elapsed time (f1f7) = 0.2 sec direction ofwave & backthrust  directionof swimming forward velocity = ?wave frequency = ?wave velocity = ?Reynolds number = ?

  14. The Formation of Vegetable Mould, through the Action of Worms,with Observations on Their Habits by Charles Darwin1881

  15. Animation of peristaltic crawling… …a follow-up to student lab inquiry about hydrostatic skeletons & locomotion without appendages in living invertebrates(e.g., terrestrial and aquatic annelid worms)

  16. circularmusclewave   CM  CM  CM  longitudinalmusclewave    LM  LM  LM

  17. ELONGATED SEGMENT:length = 17.5 mm; diameter = 13 mm volume = π · r2 · length = 2,321 mm3 SHORTENED SEGMENT:length = 7.5 mm; diameter = 20 mmvolume = π · r2 · length = 2,355 mm3 I I

  18. Open-ended inquiry with living crustaceans Artemia franciscanaNorth American brine shrimp

  19. fertilized eggs in brood sac Artemialife cycle X winter ‘eggs’ Adult female HATCH

  20. transparency strip with grid10 mm x 10 mm plastic petri dish strip of double-stick tape covers grid tape holds strip to dish

  21. “Paint” cysts onto tape with small, soft, dry paintbrush

  22. STUCK-onARTEMIATechnical Advantages easy handling & transfer of cysts uses small, quantifiable number of cysts follow development of individual cysts cysts stay in single focal plane use dissecting or compound microscope manipulation of many relevant variables

  23. Hatching of encystedArtemia embryos Encysted late gastrula stageCyst hydrates and swellsCyst wall splitsMembrane-bound“umbrella” stageNauplius larva emergence

  24. Each day, a pipet is used to remove and count hatched, swimming nauplius larvae

  25. %HATCH

  26. Experimental variablesPHYSICAL & CHEMICAL ENVIRONMENT Temperature (heating, cooling, freezing)Sun light (UV)Microwave irradiationSalinity (hypo- & hyperosmotic)Repeated hydrationDissolved oxygenToxicants (pollutants, pharmacological agents) Measurements & End-points Hatching % Hatching time-courseDevelopmental anomalies Larval motility Molting & growth

  27. Independent inquiry

  28. CONCEPTS & PRACTICAL IDEAS(non-cookbook) 1) Invertebrates as toxicity test organisms2) Selection of test chemical(s)3) Exposure / treatment protocols4) End-points (lethal versus sublethal effects)5) Concentration range-finding (preliminary expts)6) Final testing and analysis7) Materials, supplies, resource references8)SAFETY ISSUES&GLOSSARY

  29. Invertebratesare more than… …creepy, crawly novelties …taxonomic survey material …anatomy & dissection material

  30. Use of living invertebrates for biology lab inquiries… … engages & enlivens interest … makes biology more than a ‘spectator sport’ … promotes analytical thinking

  31. Take-Home Materials CD:“BIOLOGY in ACTION” - 31animations&“Freshwater Invertebrates”- PowerPtfile • Copy:Contents& AnimationQ/A’s for InstructorCopy: Student lab inquiry:“Stuck-on Artemia” Reprint:“Biological Smoke Detectors”