Texas Journal of Microscopy - Texas Society for Microscopy

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Plate 1. Biological crystals. This chart is a virtual map to the crystal trail; like the map to King Solomon’s Mines, it can guide you to many of the traditional “crystal systems” found in biological tissues. The figure was made to call attention to crystal development in both animals and plants. Despite the importance of some of these systems, in 1970 there was little broad interest in crystals, possibly because of the general thought that crystals are “inert” and not involved in the metabolism of organisms. The figure is divided both horizontally and vertically with inorganic crystals above the median line and organic crystals below it. On the upper left various animal systems are listed; on the upper right crystals of a number of plant systems are found. The figure is not meant to be inclusive but rather to deal with many of the systems that have been a part of my “crystal trail.” Egg shells (currently the end of my crystal trail) are made up of a layer of large radially oriented calcite crystals of calcium carbonate grown together and somewhat supported by a protein matrix. The regulation of egg shell thickness is a major problem for the 10 billion dollar poultry industry. Bones and teeth are formed by crystals of calcium phosphate (hydroxyapatite crystals) imbedded in a protein matrix. The extremely small crystals (crystallites) of bone are produced by osteoblasts associated with collagen fibrils. Specialized cells called ameloblasts in teeth produce long thin ribbon-like hydroxyapatite crystals in enamel prisms also embedded in protein matrix. Kidney stones represent a third important mineral system of humans and other mammals; the most common are crystals of calcium oxalate dihydrate but many are also associated with colestreol. In the ocean and in some marine deposits, the shells of molluscs are made up of calcium carbonate (both calcite and aragonite) also embedded in a protein organic matrix. Echinoderms and sponges use calcium carbonate crystals to construct parts of the their bodies; these creatures also have a protein matrix that is associated with their crystals. In plants, crystals of calcium oxalate are extrememely common. Over three fourths of plant groups produce CaOx crystals. The CaOx crystals are produced always in the vacuole, and may be found one per cell or one cell may have more that 2000 crystals. The shape of the crystals in plants seems to be under genetic control since individual species always produce the same kind of crystals. However, soil conditions can also regulate the presence or absence of crytals in certain species. Calcium sulfate crystals are found in desmids but is rare or unknown in other groups of plants. Crystals of calcium carbonate are sometimes found in the walls of various seed plants. Amorphus calcium carbonate deposits are common in approximately ten families of flowering plants. These specialized cells, called cystoliths, each have a deposite of calcium carbonate in an internal structure called a lithocyst. Occasionally, the lithocysts become crystalized through the formation of calcite crystals. Organic crystals, usually protein crystals are common in many organisms. In animals, yoke platelets and peroxisomes have organic crystal. In these crystals, the lattice plane of the protein can often be resolved. The viral diseases of insects are also associated with protein crystals which often surround one or more virus particles. The guanine crystals found in various tissues of fish (eyes and skin) are common examples of an organic crystal serving an important structural role. Protein bodies are common in the seeds of many plants; they are also found in microbodies (peroxisomes) or free in the cytoplasm. TMV and other viruses may crystalize in plant cells. One can not help but notice the routine association of proteins with crystals in many of the the systems discussed. The role of the proteins is of universal interest. Adapted from Arnott and Pautard, 1970. 20 Tex. J. Micros. 38: , 2007
Plate 2. A series of light micrographs which show the graphic colors often seen when observing plant crystal cells either directly or under polarized light. 1. Micrographs showing a cleared leaf of Ginkgo biloba. Upper figure clearing as seen in normal light, lower right figure as seen in polarized light. Note the numerous druses which occur along each vein. 2. A single styloid crystal in Eichhornia crassipies (the water hyacinth) as seen under polarized light. The styloid is contained within a cell but under these conditions the cell walls are not seen. 3. Crystal sclereids of Nymphaea as seen in normal light (left) and polarized light (right). The lower part of the sclereids has grown into the airspace of the leaf. 4. Paradermal section of a Vitis vinifera leaf showing large raphide idioblast. 5. Paradermal section of V. vinifera showing a raphide idioblast under polarized light. 6. Living section of V. vulpine showing large raphide cell with small group of crystals in its center. Tex. J. Micros. 38: , 2007 2
Page 1 and 2: TSM e Texas Journal of Microscopy V
Page 3 and 4: TSM OFFICERS 2007-2008 President: E
Page 5 and 6: President’s Message I wish to tha
Page 7 and 8: TSM e Atomic Spectroscopy Instrumen
Page 9 and 10: EPICARDIAL FORMATION IN SITU AND IN
Page 11 and 12: AN INVESTIGATION ON IN VITRO CULTUR
Page 13 and 14: Tex. J. Micros. 38: , 2007 3
Page 15 and 16: NANO/SUB-MICRON GRAIN EVOLUTION IN
Page 17 and 18: EDUCATIONAL SCIENCES SPRING 2007 IN
Page 19: Figure 2. Prince Valiant fights for
Page 23 and 24: Plate 3. Early 1960’s transmissio
Page 25 and 26: dissecting needles. Then Fred mount
Page 27 and 28: Figure 9. “Life History” of the
Page 29 and 30: Plate 6. Cytoplasmic polyhedrosis i
Page 31 and 32: Plate 7. Tapetum lucidum and iridop
Page 33 and 34: Plate 8. Iridophores of the guppy (
Page 35 and 36: Plate 10. Calcium oxalate crystals
Page 37 and 38: convenient subject since Zyznar and
Page 39 and 40: Plate 12. Cystoliths of Morus rubra
Page 41 and 42: Plate 14. Cystoliths of Morus alba.
Page 45 and 46: Plate 17. Participants in various m
Page 47 and 48: TWINNING Figure 17. Twin crystal mo
Page 51 and 52: Plate 18. Micrographs of CaOx cryst
Page 53 and 54: Plate 20. SEM of calcium oxalate cr
Page 55 and 56: she worked on the seeds of zucchini
Page 57 and 58: Plate 23. Crystals of Oxalis dillen
Page 59 and 60: Plate 25. Calcium oxalate crystal t
Page 61 and 62: Regrettably, one is obliged to live
Page 63 and 64: is seen in SEM, its surface is rela
Page 65 and 66: Plate 27. Early development in the
Page 67 and 68: Figure 35. Narrow crystals of calci
Page 69 and 70: Plate 29. Fungal crystals. 1-14. Dr
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Plate 31. Fungal crystals. 1-3. Dev
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Plate 32. Fungal raphides. 1. Surfa
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Plate 34. SEM of fungal hyphae coll
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Figure 41. Spore sac of Geastrum co
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Plate 36. Calcium oxalate crystals
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Tex. J. Micros. 38: , 2007 8
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Figure 47. Crystal sclereids of Nym
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Plate 38. Crystals of Euglena granu
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from the fish pond next to the Biol
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Arnott, H.J. 1962. The seed, germin
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Tex. J. Micros. 38: , 2007 9
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