Charlie Drewes

Biology Inquiry Biology Inquiry with Invertebrateswith Invertebrates

Ecology, Evolution &

Organismal BiologyIowa State University

Ames, IA 50011

“ I hear and I forget,

I see and I remember, I do and I

understand.”

Confucius

►► Guided inquiry “BIOLOGY in ACTION”

►► Open-ended inquiry”Stuck-on Artemia”

►► Independent Inquiry“Biological Smoke Detectors”

‘‘BIOLOGYBIOLOGY inin ACTION’ACTION’

31 Interactive & Computational

Animations

WEB-based and CD (non-proprietary)

INTERDISCIPLINARY AREAS:Biology, Math, Physics

TOPICS & FOCAL POINTS:

Locomotion BiomechanicsCell Biology Animal Behavior

Physiology DevelopmentInvertebrate Biology

adjuncts to hands-on laboratory inquiries with living organisms

adjuncts to lecture / discussion (homework or student presentations)

focal points for problem-based learning (computation & data analysis)

CURRICULAR UTILITY:

RED = interactive animations with computations and control features

BLACK = GIF animations with questions and links

LINK to CONTENTS

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►

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Lumbriculus variegatus

California blackwormAnnelida (Oligochaetea)

Hands-on Lab Investigations with Living Lumbriculus

Circulatory Function (ABT) (blood flow, pulse rate) Locomotion & Movement (ABT)

(swimming, crawling, reversal behavior)

Segment Regeneration (ABLE) (development; asexual reproduction)

Interactive format

Animations of Lumbriculus blood vessel pulsations: Adjunct to lab inquiry of circulation in living worms

0 sec0 sec

2 sec2 sec

3 sec3 sec

4 sec4 sec

5 sec5 sec

1 sec1 sec

CirculatoryComputations

pulse frequency

(pulse waves /sec) pulse velocity (mm /sec)

blood volume (cc3 / time)

TAIL TOUCH

Animation of helical swimming in Lumbriculus:

A follow-up to student lab inquiry of locomotion

in living worms

Helical swimming in Lumbriculus:

A unique form of animal locomotion

elapsed time (f1elapsed time (f1f7) = f7) = 0.2 sec0.2 sec

directionof swimming

direction ofwave & backthrust

forward velocity = ?

wave frequency = ?

wave velocity = ?

Reynolds number = ?

The Formation of The Formation of Vegetable Mould, through Vegetable Mould, through

the Action of Worms,the Action of Worms, with Observations on Their Habitswith Observations on Their Habits

by by

Charles DarwinCharles Darwin

18811881

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)

CM

circularmusclewave

CM

LM

LM

CM

LM

longitudinalmusclewave

ELONGATED SEGMENT:

length = 17.5 mm; diameter = 13 mmvolume = π · r2 · length = 2,321 mm3

SHORTENED SEGMENT:

length = 7.5 mm; diameter = 20 mmvolume = π · r2 · length = 2,355 mm3

I

I

Artemia franciscana

North American brine shrimp

Open-ended inquiry with living crustaceans

HATCH

Artemia

life

cycle

fertilized eggs in

brood sac

Adult female

X

winter ‘eggs’

plastic petri dishtransparency strip with grid

10 mm x 10 mm

strip of double-stick tape covers grid

tape holds strip to dish

“Paint” cysts onto tape with small, soft, dry

paintbrush

STUCK-on ARTEMIATechnical 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

Hatching of encystedArtemia embryos

Encysted late gastrula stage

Cyst hydrates and swells

Cyst wall splits

Membrane-bound“umbrella” stage

Nauplius larva emergence

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

0

20

40

60

80

100

day 0 day 1 day 2 day 3 day 4

%HATCH

Experimental variablesPHYSICAL & CHEMICAL ENVIRONMENT

Temperature (heating, cooling, freezing)Sun light (UV)Microwave irradiationSalinity (hypo- & hyperosmotic)Repeated hydrationDissolved oxygenToxicants (pollutants, pharmacological agents)

Measurements & End-pointsHatching % Hatching time-courseDevelopmental anomalies

Larval motility

Molting & growth

Independent inquiry

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

CONCEPTS & PRACTICAL IDEAS (non-cookbook)

InvertebratesInvertebrates are more than…

…taxonomic survey material

…anatomy & dissection material

…creepy, crawly novelties

Use of living Use of living invertebrates for invertebrates for

biology lab inquiries…biology lab inquiries…

… makes biology more than a ‘spectator sport’

… engages & enlivens interest

… promotes analytical thinking

Take-Home MaterialsTake-Home Materials

CD:CD: ““BIOLOGY in ACTION”BIOLOGY in ACTION” - - 3131 animationsanimations & “Freshwater Invertebrates” - PowerPt- PowerPt filefile

Copy:Copy: ContentsContents & Animation& Animation Q/A’s for InstructorQ/A’s for Instructor Copy: Copy: Student lab inquiry: “ Stuck-on Artemia” Stuck-on Artemia” Reprint:Reprint: “Biological Smoke Detectors”