POLYPHOSPHATE AND SILICEOUS GRANULES IN THE GAMETOPHYTES OF THE RED ALGA <i>PORPHYRA PURPUREA</i> (BANGIOPHYCEAE)
Bibliographic record
Abstract
Variations of the different phosphorylated fractions in tissues of starved and fresh plants of Porphyra purpurea, a representative of the Bangiophyceae, over a 72 hour incubation period in pulse‐enriched seawater (15 μM phosphorus and 25 μM nitrogen) were analyzed and compared to those in Chondrus crispus, a representative of the Florideophyceae, considered the more advanced of the two classes of the Rhodophyta. Differences point towards P. purpurea being a much more metabolically active phosphorus “pump” than C. crispus, with a higher phosphorus turnover rate, in which the orthophosphate fraction is predominant and acid‐soluble and acid‐insoluble polyphosphates are not as significant storage pools. Confirmation of the presence of acid‐insoluble polyphosphates, detected by chemical analyses, in the form of cytoplasmic granules was obtained by transmission electron microscopy and energy dispersive X‐ray microanalysis. The granules in P. purpurea were, however, much smaller (20 to 110 nm in diameter) than those in C. crispus (around 1 μm, but some larger than 2 μm in diameter). Larger granules (290 to 310 nm in diameter) were also observed. Their surface was more uniformly electron‐opaque without the reticulated or globular appearance of typical polyphosphate granules. Energy dispersive X‐ray microanalysis demonstrated that they were siliceous granules. To our knowledge, this is the first report in algae of such structures whose occurrence and metabolic role remain enigmatic.
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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) | 0.000 | 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".