Acorn parts

Prepare plant extract. Grind material (acorn parts, bud scales, bark, or leaves) into fine powder. Extract 100 mg material (ground acorn tips or bases, or powdered bud scales) in 0.5-ml MeOH/HjO (50 50) [or a 70% acetone-MeOH mixture] for 1-3 h at room temperature. Pipette off supernatant. 

We can now consider the place of special chemicals in the lives of these organisms. Some of these chemicals link different organisms and others act within individual species. Chemicals in the first group participate directly in the biological chain between acorns and ticks. Those in the second group contribute to a particular species success and so influence these interactions indirectly. All the chemicals are a normal part of these creatures lives and all have a meaningful place here. We begin with oaks and then deal with the animals. 

Remains of acorns of red oak, Quercus rubra, after gray squirrels, Sciurus carolinensis) have been feeding on them. Top row. cross section of acorn, with radicle barely visible at apical pole at the bottom. Middle row. Parts of acorns left behind by squirrels. They discard apical pole (with radicle visible). Such pieces are later consumed by birds such as blue jays (Cyanocitta cristata). Bottom row. pieces of acorn shells. Photo D. MiiUer-Schwarze... 

Tannin levels vary within an acorn. They are more concentrated in the apical (pointed) portion with the embryo. Accordingly, gray squirrels, and also grackles and jays, selectively consume more often the basal part of an acorn than the distal part (Steele et al. 1993). The embryo will still germinate after being left over by a squirrel. The chemical gradient in the acorn may represent an adaptation that results in a compromise animals consume only the part of the acom that contains the least tannin, but the better protected seedling and parts around it will still survive the predation. 

The material analyzed in this exercise can be known amounts of tannins such as tannic acid (a mixtnre of tannins), or plant extracts with unknown amounts of tannin. This exercise is written for tests with plant materials whose tannin level we wish to determine. These can be bnd scales of trees such as aspen, or different parts of acorns (tip vs. base). 

Cu pule.—Applied to the concave involucre enclosing the glans of an acorn but also to other cup shajjed parts of plants. 

The Primordial Pangk and Amrta PART four Appendices, Bibliography, Index, Acknowledgements APPENDIX A Sundry Visionary Compounds I. Asarones 6. Acorns calamus... 

Standard hexagon nuts are used with bolts to fasten parts together. Where parts require to be removed frequently and hand tightness is sufficient, wing nuts are used. Fig. 13.5(a). If a decorative appearance is required, a dome or acorn nut can be fitted, Fig. 13.5(b). 

Barnacles. After mussels, we probably know the most about how the common acorn barnacle makes its cement. You can see barnacles on a rock in Figure 13.8. Here, too, the material is based on cross-linked proteins. However, there is no DOPA in the barnacle cement proteins. Perhaps the thiol groups of cysteine amino acids (i.e., RSH groups) are oxidizable to disulfides and take part in an oxidative protein cross-linking to form barnacle cement, although we do not yet know for sure. Hair perms rely on just this type of disulfide formation to link hair and hold it in a given configuration. Barnacle... 

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