Consulta: creatorFacets:"Paiva,Elder Antônio Sousa"
Registros recuperados: 2
Data/hora: 02/06/2024 03:44:32

How does the nectar of stomata-free nectaries cross the cuticle?
Provedor de dados: Acta Botanica Brasilica
Autores: Paiva,Elder Antônio Sousa.
ABSTRACT In many glandular structures, departure from the cell is only one step in the process of exudate release to the plant surface. Here the set of events that lead nectar to the external environment is presented and discussed mainly for stomata-free nectaries. After being synthesized, the nectar or some of its component needs to be released to the environment where it performs its functions. Nectar precursors derived from cell metabolism need to cross several barriers, such as the cell membrane and cell wall, in order to become nectar. Then the nectar must cross the cuticle or pass through stomata in order to be offered to plant mutualists. Release through stomata is a simple mechanism, but the ways by which nectar crosses the cuticle is still...
Palavras-chave: Animal-plant interactions; Cuticular pores; Nectar; Nectar release; Plant secretion.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062017000300525

Role of intermediary cells in Peltodon radicans (Lamiaceae) in the transfer of calcium and formation of calcium oxalate crystals
Provedor de dados: Brazilian Archives of Biology and Technology
Autores: Paiva,Elder Antônio Sousa; Machado,Silvia Rodrigues.
With the objective of studying the connection between calcium oxalate crystals formation and the phloem, fragments of leaves of Peltodon radicans Pohl (Lamiaceae) were fixed and processed, for light and electron-transmission microscopes. It was observed that the crystals occurred in the cells of the bundle sheath, juxtaposed in relation to the phloem. Intermediary cells established a connection between the sieve element and crystal-bearing sheath cells. Calcium was present abundantly in the cytoplasm of sheath cells as calcium oxalate crystals. The presence of calcium was also detected in the intermediary cells, but in the sieve elements it was not detected. There was, therefore, an increasing concentration gradient of calcium in the sieve elements from...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Calcium oxalate; Calcium metabolism; Companion cells; Crystals; Peltodon radicans; Phloem.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132005000100019