Project/Area Number |
03804057
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
植物形態・分類学
|
Research Institution | kagawa university |
Principal Investigator |
TAKAHASHI Masamichi Kagawa Univ Biol ASS Prof, 教育学部, 助教授 (00154865)
|
Project Period (FY) |
1991 – 1992
|
Project Status |
Completed (Fiscal Year 1992)
|
Budget Amount *help |
¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1992: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1991: ¥1,200,000 (Direct Cost: ¥1,200,000)
|
Keywords | Pattern determination / Exine / Plasma newbrane / Angiosperm / Ultrastructure / Freeze fracturve / パタ-ン決定 |
Research Abstract |
Exine development was studied using high resolution scanning electron microscopy, with attention to the initial developmental process of protectum formation and composition. The protectum is originated on the protuberant sites of the invaginated plasma membrane during the early tetrad stage. The present study shows that the initial protectum is composed of irregularly oriented fibrous threads. The fibrous threads accumulate and form a network on the plasma membrane. Globular materials gradually aggregate within the network of fibrous threads during the tetrad stage. Subsequently the fibrous threads are almost masked by the globular materials. The developing protectum has a coarse texture within the callosic tetrad envelope. At the free microspore stage the granular protectum becomes homogeneous. The present study suggests that the protectum consists of an association of fibrous threads and globular material. The fibrous threads may function as receptors and/or the skeleton of the developing exine.
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