<<

I How-To-Do-

.Bag of Bonesi

RichardA. Menger

Frequently I'm asked for the tech- same bag with a 5% nique that I've used to mount the aqueous solution of Scapula demonstration skeletons used in my sodium chloride. To classroom. My technique was modi- this solution add a Downloaded from http://online.ucpress.edu/abt/article-pdf/56/4/240/46565/4449804.pdf by guest on 24 September 2021 fied from Dr. Hans Gruneberg's The good pinch of papain ) Scapular Geneticsof the Mouse, and is the most (amount depends on time conservative and effective size of skeleton). Zip method I've seen anywhere. This the bag closed, shake Clavicle Apn method utilizes a proteolytic enzyme, it, and place it in an papain, which is derived from the incubator at 38-40'C tropical papaya fruit. (Papain may be for 24 hours. purchased from Difco Laboratories, The next day, shake Box 1058, Detroit, MI 48232.) It costs each bag again vigor- approximately$80 for 500 grams. This ously to loosen any quantity lasts a long time. The proce- tissue still remaining dure is recommended for any size an- on bones. Rinse the imal that is medium-dog size or bones once or twice in smaller. This size is restricted only tap water while still in because of the size of Ziploc? bags the bag to, again, free available and display requirements. bones of any tissue First, completely skin and eviscerate still remaining. Great the specimen. Then section care should be taken into head, limbs, trunk and tail. While not to lose any of the sectioning, also remove the larger little bones as the so- muscles from the legs, and remove the lutions are poured off. tongue, eyes and brain from the skull. Do not allow the No scraping is necessary, since the bones to dry with tis- proteolytic enzyme will take care of sue still adhered to the rest. After rinsing in tap water, them. Keep all bones place each section in an appropriate- submerged while any sized Ziplocg bag, which can be either solution is used in the Claws~} Phalanges quart, one-gallon or two-gallon size. bags. Make sure to label each bag. The bones are then A section might be similar to Figure bleached by placing 1 and be labeled left shoulder girdle them in hydrogen Figure 1. Typical "bagged" section might be labeled left and arm. Sectioning and bagging will peroxide in the same armsection. save you an enormous amount of time bag for about five because you won't have to sort hours. Placing the one big pile of bones. bags during this time in direct sunlight cong or Dupont? works best, because Cover each section within the bag will hasten this portion of the proce- these are clear), or lay them out in with tap water and double boil it for 10 dure. order on black art paper, gluing them minutes in a large kettle. You should Then, after pouring off the hydro- in place with the contact cement. La- now have five to six bags boiling at the gen peroxide solution, replace with beling can be neatly done in a variety same time. Carefully pour off the acetone in the same bag for 12-24 of ways. Stainless steel rods of a quar- boiled water and cover again in the hours. This will remove any grease ter-inch or better in diameter can be and fat and prepare the bones better used for support, as well as wire of for gluing. Following this, empty each different gauges to mount on a wood bag onto paper toweling and allow the base. Any bones connected in the RichardA. Menger teaches biology at can be loosened with ac- Baker High School. An OBTAwinner in contents to dry. wrong place 1986, Menger can be reached at P.O. Students may either assemble the etone. Box659, Baker,MT 59313. skeleton in a standing position with Besides the satisfaction a student wire and Ducog contact cement (Dev- gets by using this technique, it may

240 THEAMERICAN BIOLOGY TEACHER, VOLUME 56, NO. 4, APRIL1994 be applied to research problems such This Bag of Bonestechnique may be larvae. My students have mounted as: used for the preparationof any skele- animals ranging from shrews to coy- ton, but larger animals require more otes, and everything between. A rac- 1. Effects of vitamins, hormones papain and larger Ziplocg bags, and coon eating a frog and a coyote chas- and respiratory gases on bone have to stay in the various solutions ing a rabbit are two of the more development for longer periods of time. The use of interesting specimens. You'd be sur- 2. Rates of bone growth Ziplocg bags, papain and the related prised how fast a collection grows 3. Strain skeletal differences procedure is quick, convenient and and the time saved by using Bag of 4. Genetic variations. less odoriferous than relying on beetle Bones. Downloaded from http://online.ucpress.edu/abt/article-pdf/56/4/240/46565/4449804.pdf by guest on 24 September 2021 Teaching Critical Thinking Skills in Biolog

With the emphasis on science reform and the recent examples of strategies, techniques and exercises in a findings of research on learning, many classroom teach- variety of biology topic areas. It also illustrates how ers have begun to focus on new strategies for develop- standardized tests require critical thinking skills. ing students' ability to think critically as they analyze The authors, Robert D. Allen, Ph.D., vice president scientific knowledge. of instructional services at Victor Valley College, Teaching Critical Thinking Skills in Biology, the Victorville, CA, and David J. Stroup, Ph.D., depart- newest monograph published by the National Associa- ment of biology, Francis Marion University, Florence, tion of Biology Teachers, presents guidelines, ex- SC, have worked together for more than 15 years amples and procedures that will help biology teachers focusing their instructional research on development incorporate the teaching of critical thinking skills into of students' critical thinking skills. They have pre- their lessons. The 56-page monograph discusses the sented more than 40 national workshops on the topic. importance of critical thinking, and offers numerous Order your copy today!

Teaching Critical Thinking Skills in Biology Order Form [ ] Yes! Pleasesend me _copy(ies) of Teaching Critical Thinking Skills in Biology.

Name

Address

Phone

Amount due: $15 for NABT members/$20 for nonmembers $ Plus shipping and handling ($2 for 1-2 items, $4 for 3-5 items, $6 for 6+ items) $ Add $4 additional shipping per copy for air mail outside U.S. and Canada $

TOTAL AMOUNT DUE $

[ ] Check drawn on U.S. bank or international money order (payable to NABT) enclosed

[ ] Charge: VISA or MasterCard (Circle one) Card #

Exp. Date Signature

Complete this form and mail to: NABT, 11250 Roger Bacon Drive #19, Reston, Virginia 22090

BAGOF BONES 241