Microsporogenesis in<i>Amelanchier alnifolia</i>: sporogenous cells, microsporocytes, and tetrads
Bibliographic record
Abstract
As part of an overall program aimed at increasing our knowledge of the male reproductive system of Amelanchier alnifolia Nutt., this study documents structural and developmental changes that occur in the sporogenous cells, microsporocytes, and tetrads of microspores during microsporogenesis using general cytochemical techniques in conjunction with bright field, fluorescence, and transmission electron microscopy. The sporogenous cells are thin walled and stain positively for β-1,4-glucans, pectic acids, and cellulose, but not callose. At the microsporocyte and tetrad stages of microsporogenesis, thick walls develop and stain positively for β-1,4-glucans (hemicelluloses but not cellulose), pectic acids, and callose. Thus, the eventual release of maturing microspores from the tetrads requires the digestion of all three of these carbohydrate wall materials. Postmeiotic cytokinesis is of the simultaneous type and is initiated when Golgi vesicles aggregate simultaneously into a network of cylindrical tubules in both central and peripheral cell locations of the coenocytic tetrad. Eventually, this network fuses to form the new cell walls within the microspore tetrad.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".