Life Science Tactile Graphics Teacher’s Guide Fred Otto, Author and Project Co-Leader Rosanne Hoffmann, Project Co-Leader Katherine Corcoran, Model/Pattern Maker Tom Poppe, Tooling Advisor David McGee, Technical Assistant American Printing House for the Blind 1839 Frankfort Avenue P.O. Box 6085 Louisville, Kentucky 40206-0085 ?2010 The project leaders thank the following teachers for their time, attention, and creative comments in field evaluating Life Science Tactile Graphics: Denise Adelmann, Peggy Bergman, Trina Britcher, Sharon Clark, Katie Culbertson, Barbara French, Lis Geoghegan, Meridith Hoisington, Cindy Miller, Faye Rahni, Alan Roth, Christy Shepard, Wendy Stoltman, Janet Ulwick-Sacca, and Laurel Van Dyke The following are APH staff or visitors who also participated in our “Tactile Graphics On Friday” sessions and whose drawing ideas made their way into the diagrams included in this set: Kevin Devine, Dena Garrett, Jayma Hawkins, Loana Mason, Laurianne Matheson, Karen Poppe, Carol Roderick, Erica Rucker, Anita Rutledge, Monica Vaught-Compton, and Yan Zhang TABLE OF CONTENTS 1 Light or Compound Microscope 2 Cell Sizes and Shapes 3 Comparing Animal and Plant Cells 4 Mitochondrion 5 Chloroplast 6 Prokaryotic Cell 7 Bacterial Types 8 DNA 9 DNA Double Helix 10 DNA Replication 11 Translation 12 Chromosome Duplication 13 Cell Cycle Chart 14 Mitosis 15 Meiosis I 16 Meiosis II 17 Non-Disjunction in Meiosis I 18 Non-Disjunction in Meiosis II 19 Fertilization 20 Viral Replication 21 Membrane Transport 1 22 Membrane Transport 2 23 Pedigree 24 Forelimb Bones 25 Comparative Embryology 26 Skin Cross-Section 27 Neuron 28 The Eye 29 The Ear 30 Using Lenses for Vision Correction 31 Sense of Taste 32 Leaf Cross-Section 33 Tree Canopy & Roots 34 Vascular Structure of Wood 35 Plant Intake and Output 36 Moss Life Cycle 37 Fern Life Cycle 38 Pine Life Cycle 39 Parts of a Flower 40 Monocot and Dicot Seeds 41 Seed Germination 42 Sponge 43 Sponge Life Cycle 44 Cnidarian Stinging Cell 45 Cnidarian Life Cycle 46 Flatworm and Roundworm 47 Snail Body Plan 48 Insect Metamorphosis 49 Insect Feeding Adaptations 50 Fish Internal Organs 51 Fish Skeleton 52 Amniotic Egg 53 Bird Flight Adaptations 54 Water Cycle 55 Carbon Cycle 56 Food Web Introduction Life Science Tactile Graphics are vacuumformed raised-line drawings depicting organisms, processes, concepts, and patterns which are typically covered in middle- and high-school life science courses. They are intended to supplement, not replace, the graphics in a student's classroom textbook. These graphics may offer students a different presentation from their brailled textbook graphics. The emphasis in this adaptation is on tactual readability rather than adherence to a particular printed image, although scientific accuracy is always maintained. Because these graphics are not identical to any image found in a particular science text, they may not contain all of the same features as a given textbook graphic. Thus, these vacuumformed graphics and the student's braille textbook together make a good combination. Lines and Textures The drawings in Life Science Tactile Graphics include many types of lines and textures, as well as surfaces of different heights. In general, higher or more tactually prominent ("loudest") textures signify the most important features of the diagram. While it might seem preferable to give certain lines and textures the same meaning throughout the set, the limited selection of readable textures and the complexity of the graphics combine to make this goal impractical. As a result, lines and textures should be interpreted within the context of each diagram. For example, similar textures may be used to indicate the soil in a plant diagram, a component of the skin in another diagram, and the surface of a sponge in another. Teaching Suggestions All of the drawings in Life Science Tactile Graphics set depict concepts, systems, or terms that are common to any basic course in life science. Instructional hints are given for some of the tactile drawings in the set. They focus on how you might present the concepts to students who are blind and what these students might find most challenging about the drawing or the concept. The goal of the suggestions is to help you as you try to make science learning real for students who are not using the standard printed images. It is rare to find a tactile picture that stands on its own for the blind student to understand without explanation from the teacher. Even the most well-crafted tactile graphic cannot overcome the fact that perceiving through touch is different from perceiving with sight, and things that are easily apparent with sight are usually less apparent through touch. These graphics may help demonstrate concepts in science just as print pictures do, but they always depend on the verbal description or physical demonstration that you provide to be effective. In other words, the graphics don’t teach science concepts—you do! Consider the range of pictures found in science books. They present front, side, overhead, and interior views, pictures of things real and imagined, and a scale from the microscopic to the cosmic. With sight, you can look at a picture and instantly recognize the perspective—the essence of how the information is presented—and, within this context, quickly focus on details of what is being conveyed. Using touch, this immediate grasp of the whole of the picture is not available. The whole must be pieced together with time and exploration. As a teacher, you can help students read a tactile graphic by explaining how the graphic is presented and what it shows; for example: "This shows the plant at different times at different stages of the reproductive cycle," or "This is how the cell looks magnified thousands of times under a microscope." These different kinds of views require explanation and demonstration, because, as stated before, it takes time and practice to translate the many ways things can appear to the sense of sight into a worthwhile tactual experience. Print graphics, and those in this set, show things from many different perspectives. For instance, you can look down on an insect from above, as if it rested on the table; you can look at a plant from ground level, seeing its leaves and its roots at the same time; you can see the vast ocean floor as it stretches from one continental shelf to another; you can see an organism developing from one stage to the next; and so on—all in pictures. With exposure and practice, we gain the ability to interpret and connect these images to a reality we are familiar with. Students who lack experience and practice will need some creative assistance from you to make these images “real.” The issue of magnification also deserves special mention. In print textbooks, pictures often are not identified as magnifications because it's assumed that students can recognize them as such. (These pictures are often shown with a round frame to suggest a view through a microscope.) This set of graphics assumes the same ability for blind readers, but you should be alert for opportunities to reinforce their understanding of the relative scale of the items pictured. Many of the diagrams in this set contain arrows, which serve different purposes depending on the context. In general, thin, dashed-line arrows indicate the transition from one stage in a cycle to another. These diagrams show the first stage of the cycle at the top left or top center of the page, and subsequent stages (indicated by the arrows) moving clockwise or downward on the page. In contrast, a thicker arrow is generally used to show the actual motion of one substance into or away from another. Students may need specific training in reading and following arrows, depending on their previous experience with tactile diagrams. The Table of Contents lists the tactile graphics in subject groups which may suggest ways they can be taught. Keep in mind that when you use these tactile graphics, you are not only teaching students life science, you are helping them to use and interpret tactile pictures in general. As you build up students’ competence and comfort in reading graphics, you open up possibilities for them and prepare them for further academic success. Along the way you will introduce many concepts and, with luck, stimulate students to be active thinkers (that is, scientists). Notes on the Diagrams Following are some brief notes on the tactile graphics in this set, giving some considerations that may be helpful in your teaching. 1 Light or Compound Microscope This simple diagram shows the components of a standard classroom microscope. While the actual tool may be of little use to blind students, microscope diagrams are often seen on standardized tests, and all students should become familiar with the basic parts and terminology. 2 Cell Sizes and Shapes This diagram shows that cells are not uniform, either in size or in shape; these are related to their particular function. 3 Comparing Animal and Plant Cells This is the first illustration in the set that relies on a key for the abbreviated labels. The two cells are placed on the same page for easy comparison of their components. 4 Mitochondrion 5 Chloroplast Because these organelles are shown in cutaway view, students may need coaching to understand that they are really enclosed structures within a cell. 6 Prokaryotic Cell The thickness of the cell’s boundary is greatly exaggerated in this image because of the need to make the cell membrane, cell wall and capsule all tactually distinctive from each other. 7 Bacterial Types These highly magnified views give students the opportunity to see the bacteria in isolation and in colonies. 8 DNA 9 DNA Double Helix The first diagram shows the DNA ladder and introduces the pairings of the bases. Students should note the way these pairings are typically shown, namely, with pointed and rounded bases and their correspondingly shaped receptors. The second diagram may be used in conjunction with a 3-D DNA model to show how a complex spiral structure can be represented in a book. 10 DNA Replication 11 Translation These diagrams depict processes, that is, changes that take place within the structures shown. Students may need specific instruction to see an illustration as a series of steps rather than as a static image. 12 Chromosome Duplication Although this is a simple picture, it is a chance for students to study and memorize the shapes of the single and paired chromosomes, which will be shown extensively (in smaller forms) in later diagrams. 13 Cell Cycle Chart This chart is one of the few illustration that depict an abstract sequence rather than an actual object or structure. The most immediate comparison to make is to a clock face, with the sections representing relative time intervals. 14 Mitosis 15 Meiosis I 16 Meiosis II 17 Non-Disjunction in Meiosis I 18 Non-Disjunction in Meiosis II The important task for students using these diagrams is to be able to follow the arrows, and to note the changes—which are sometimes very subtle—from one stage to the next. 19 Fertilization This process, unlike others shown, begins with two “streams” on the left, one above the other, which combine into one as the reader moves across the page. 20 Viral Replication Because viruses are so varied in their forms, they are represented here by an abstract, easily discerned shape (a triangle). The DNA strands are also greatly simplified to reduce tactual clutter. 21 Membrane Transport 1 22 Membrane Transport 2 Each of these complex graphics shows more than one process on the same page. It is important for students to see that the long columns represent only a segment of a cell membrane; that is, if the diagram continued these columns would join to form a complete enclosure. The left side of the page stands for the inside of the cell. Since the whole cell is not shown, you may wish to illustrate this arrangement with a model or a hands-on enactment of the process. In the first diagram, the sizes of the particles passing into and out of the cell membrane are relevant. The smallest particles are shown passing through directly, while the larger ones are shown going through the protein channels, which serve as “tunnels” to help the process along. In the second image, the detailed view of the two lipid layers given in the first picture is replaced with a pair of thick lines. Students need to know that this simplified representation corresponds directly to the cell membrane shown in the previous diagram. 23 Pedigree This chart does not illustrate any particular relationship; rather, it is a general example of the layout used to organize information about inherited traits. 24 Forelimb Bones 25 Comparative Embryology These diagrams illustrate both the important distinctions and the striking similarities in their subjects, and require fine discrimination and comparison skills from students. 26 Skin Cross-Section At the right of this image are labels with lines indicating the range of the thin epidermis and much thicker dermis. 27 Neuron Students should examine the left and right sides of the structure to see that, while they are similar, they have major differences. 28 The Eye 29 The Ear Because of the complexity and closeness of the structures in the eye and ear, these images are very simplified. The eye, in particular, is difficult to portray tactually, because the tactile graphic loses the depth and dimensionality of the actual eyeball, pupil and lens. Comparing the diagrams with larger 3-D models will help students understand their features better. 30 Using Lenses for Vision Correction This diagram shows two “before and after” scenarios, again with much simplification and size exaggeration for better tactual readability. Help students understand that the light rays coming from the “T” shaped object are actually intangible, but must be represented by solid lines in the diagram. The essential point to emphasize is the ability of the lenses to focus the light rays (and thus the perceived image) directly on the retina, as opposed to in front of or behind it. 31 Sense of Taste The separate images in this graphic show the papillae of the tongue from two angles—from above, as a mass of bumps on the tongue, and from the side, greatly magnified and in cross-section. 32 Leaf Cross-Section The cells in a section of a leaf are depicted in several ways here; the common feature among them is a small depression indicating the nucleus. Note that the vascular bundle, usually shown in print as a circular structure, is partly cut off to allow direct labeling of the xylem and phloem. 33 Tree Canopy & Roots This image shows that the unseen part of a typical tree, the root system, can be as extensive as the branches rising above. Though the top of the ground is shown, this perspective magically allows us to see through it and view the entire tree as if we were a short distance away. 34 Vascular Structure of Wood Because the tactile image lacks three-dimensionality, it cannot adequately show how the vessels are arranged within the wood. The lower parts of the diagram show both an end view and a side view of the vessels, but models that are held in hand will make the comparison clearer. 35 Plant Intake and Output The graphic represents a typical leafy plant and the processes of gas and water exchange that occur. 36 Moss Life Cycle 37 Fern Life Cycle Help students recognize that these illustrations are made from the “bug’s eye view,” that is, at or near ground level. From this perspective, the horizontal line thus divides what is above ground from what is below. 38 Pine Life Cycle Hands-on comparison of the diagram to an actual pine cone with opened scales may make the life cycle more understandable. 39 Parts of a Flower Like the previous diagram, this shows the importance of a pollen tube for conducting sperm to the ovaries of the plant. The inset shows a magnified cross-section of the ovule and ovary. 40 Monocot and Dicot Seeds 41 Seed Germination These diagrams allow students to compare some of the similar and contrasting features of monocot and dicot seeds and plants. The second diagram is another ground level perspective with the soil “cut away.” 42 Sponge 43 Sponge Life Cycle The sponge diagrams depict, in various ways, the outer wall, inner wall and inside the wall itself of a typical sponge. This change in views may present difficulty for blind students and require additional explanation. 44 Cnidarian Stinging Cell 45 Cnidarian Life Cycle Because most blind students will not have seen or felt an example of a cnidarian, you may need to find models or create substitutes that convey the unusual nature of these creatures. 46 Flatworm and Roundworm Note the paired lead lines connecting the labels to the images. The purpose of the diagram is to show the features these types of worms do and do not share. 47 Snail Body Plan Drawings of snails and molluscs differ in the way the internal organs are arranged. This drawing is laid out to make the parts easily discernible and uncluttered. 48 Insect Metamorphosis The perspective in this drawing is from water level, allowing us to see above and below the water’s surface at the same time. Students may need to be introduced to the concept of water tension, which allows the eggs to sit on top of the water and the larvae and pupae to hang below the water. 49 Insect Feeding Adaptations Three types of insects, each with a different apparatus for feeding, are shown. Although not all of the organs are labeled, students should note that all three have eyes and antennae of different sizes. The differences in feeding apparatus relate to the types of food the insects consume. 50 Fish Internal Organs In this diagram, the organs are arranged to give an indication of what they are rather than for strict accuracy. This retains the essential information while making the diagram readable. 51 Fish Skeleton For both fish diagrams, be sure to orient students to the eye and mouth on the left side, which can serve as reference points for understanding the entire body plan. 52 Amniotic Egg For students who are adventurous, examining the contents of a real egg and comparing them with the drawing may give a better idea of the structures contained inside the shell. 53 Bird Flight Adaptations Along with the skeletal structure of the bird, this diagram shows two additional features that contribute to a bird’s flight ability: The air sacs that accompany the lungs, and the air spaces within the bones that make them light. 54 Water Cycle 55 Carbon Cycle Two approaches are used for these diagrams, to give students exposure to different ways of representing similar information. The first graphic is in picture form and shows the movement of water through a landscape. The second graphic presents its information more abstractly as a system of labeled arrows with no objects pictured. Both present a “ground line” perspective to the reader. 56 Food Web Students should be aware that the examples chosen are typical, but that other animals or insects could be substituted and the web made much more complex. The arrows in this kind of diagram have a special meaning because, rather than indicating motion, they signify that one kind of creature is consumed by the other. 21