Endothecium - anther wall layers, Biology

Endothecium - Anther Wall Layers

The layer of cells lying immediately next to the epidermis is the endothecium, which is responsible for the dehiscence of the anther. It is usually single-layered, but sometimes multilayered as in Nicotiana tabacum. You may recall that the endothecium originates from the PPCs. The endothecium mostly differentiates in the four protuberant or bulging parts of the anther. Sometimes, it also develops near the connective region of the anther. In some plants like Triticale an entire ring of endothecium is present.

1998_Endothecium.png

Figure: (a) Diagrammatic sketch of the transverse section of an anther showing the position of the endothecium (small arrows). Large arrows point to the two dehiscing regions of the anthers showing longitudinal dehiscence. (b) A few endothecial cells enlarged to show the characteristic endothecial thickenings.

The endothecial cells are radially elongated. Their full development is attained by the time the anther is ready to dehisce to discharge the pollen grains. At maturity the endothecial cells can be easily recognized by the presence of fibrous bands. They usually arise from the inner tangential walls. The fibrous bands radiate outwards and upwards ending near the outer wall of each cell. Hence, the inner tangential wall appears thick, whereas the outer tangential wall appears thin. These thickenings contain a high proportion of cellulose and a small amount of pectin.

Posted Date: 1/23/2013 12:24:59 AM | Location : United States







Related Discussions:- Endothecium - anther wall layers, Assignment Help, Ask Question on Endothecium - anther wall layers, Get Answer, Expert's Help, Endothecium - anther wall layers Discussions

Write discussion on Endothecium - anther wall layers
Your posts are moderated
Related Questions
In this 1st step, the corresponding  aminoacyl-tRNA for  the  second  codon  binds  to  the  A  site  by  codon-anticodon interaction.  Binding  of  the  aminoacyl-tRNA needs  elon

define zoology

Q. What is the ADP phosphorylation? What respectively are oxidative phosphorylation and photophosphorylation? ADP phosphorylation is the addition of one inorganic phosphate in

Explain the Disadvantages of Fixation? Fixation has following disadvantages also. These are highlighted herewith: (i) It distorts the cell's appearance. (ii) Motility can

Q. Show the Artificial Keys? These are based on the resemblances and differences of some prominent characters in the taxa. These are based on the phylogenetic relationship b

Define the meaning of Vital signs Vital signs are measures of different physiological statistics, often taken by health professionals, in order to assess the most basic body f

What process causes oxygen to pass from the alveoli into the lung capillaries? Diffusion is the process by which oxygen passes from the alveoli to the lung capillaries.

what are some adaptations of flatworms


Classes of Life Form The five life form classes are: Phanerophytes, Chamaephytes, Hemicryptophytes, Cryptophytes, and Therophytes.