Primary module determinate

T Vegetative primary module (determinate) Pleurocarpous perichaetial module... 

Terms such as stolon, primary and secondary stem, and branch, have often been used without careful attention to the role of the apical cell in formation of each of these features. Consequently, a primary stem in one taxon may equate to a stolon in a second, and a branch in a third, while a secondary stem may be the continuation of the primary stan but with a different orientation, a new primary module, or a secondary module (a branch ). This lack of clarity reduces the information content of these terms and makes structural comparisons between taxa difficult or meaningless, especially for determination of homology in cladistic analysis. 

A typical example of a dendroid plant in the hypnanaean pleurocarps is provided by Tham-nobryum alopecurum (Appendix 14.Ij). Here the primary modules are determinate (1), pla-... 

By producing determinate or indeterminate branches at the level of primary module sympodial branching is reiterative. It is full reiteration rather than partial reiteration. The new primary module produced in this way has the potential to produce all the subsidiary branches and structures of lower hierarchical levels characteristic of the species (i.e., the components of the architectural unit). Sympodial branching then produces new architectural units. Less commonly sympodial branching may also produce shoots at other hierarchical levels, but the most important level for moss structure is that of the primary module. 

Camptochaete arbuscula (Figure 15.3A) has an architectural unit made up of a primary module, consisting of a stolon, stipe and frond axis secondary modules, determinate lateral branches of the frond axis, the frond axis and the lateral branches together making up the frond tertiary modules, determinate lateral branches of the secondary modules perigonia and perichaetia (lateral on secondary fertile axes on the frond axis) and flagelliferous frond axis tips which become... 

In the truly pendant Weymouthia mollis (Figure 15.3B), the architectural unit consists of a primary module with somewhat distant determinate lateral branches. Reiteration is by distal lateral innovation. There is no stipe development, but there is leaf differentiation between the main axis (primary module) and the lateral branehes (seeondary modules). 

The ability of a GC column to theoretically separate a multitude of components is normally defined by the capacity of the column. Component boiling point will be an initial property that determines relative component retention. Superimposed on this primary consideration is then the phase selectivity, which allows solutes of similar boiling point or volatility to be differentiated. In GC X GC, capacity is now defined in terms of the separation space available (11). As shown below, this space is an area determined by (a) the time of the modulation period (defined further below), which corresponds to an elution property on the second column, and (b) the elution time on the first column. In the normal experiment, the fast elution on the second column is conducted almost instantaneously, so will be essentially carried out under isothermal conditions, although the oven is temperature programmed. Thus, compounds will have an approximately constant peak width in the first dimension, but their widths in the second dimension will depend on how long they take to elute on the second column (isothermal conditions mean that later-eluting peaks on 2D are broader). In addition, peaks will have a variance (distribution) in each dimension depending on... 

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