Endothecium - anther wall layers, Biology

Assignment Help:

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.


Related Discussions:- Endothecium - anther wall layers

Protozoan slides, Protozoans are a group of animal protists of more than 50...

Protozoans are a group of animal protists of more than 50,000 species and are found under almost all natural conditions where there is moisture. A protozoa11 is not as simple an or

Explain the techniques of operation in post myocardial, Explain the Techniq...

Explain the Techniques of Operation used in post myocardial infarction ventricular septal defect? Normal 0 false false false EN-IN X-NONE X-NONE

Determine the modification of food starches, Modification of Food Starches ...

Modification of Food Starches Positive attributes of starches can be greatly improved and/or negative characteristics diminished by slight and relatively simple modifications.

Deficiency diseases-predisposing factors, Predisposing factors The inc...

Predisposing factors The incidence of metabolic diseases in cows and buffaloes increases as the milk production increases and the herd size becomes larger. The highest inciden

Why is aids difficult to prevent by vaccination, Q. Why is AIDS difficult t...

Q. Why is AIDS difficult to prevent by vaccination? It is not easy to produce a vaccine against AIDS because the HIV is a highly mutant virus. In approximately every replicatio

Anticodon, Anticodon is the series of three nucleotides on the transfer RN...

Anticodon is the series of three nucleotides on the transfer RNA molecule which recognizes and pairs with the specific codon on a messenger RNA molecule; it helps in controlling t

Factor influencing lipid oxidation - temperature, Factors affecting lipid o...

Factors affecting lipid oxidation Temperature In general, the rate of oxidation increases as the temperature is increased. Temperature also influences the relation betw

Explain the completed test - most probable number test, Explain the Complet...

Explain the Completed Test - Most Probable Number Test? Coliform colonies on EMB or Endo agar are further examined by completed test by inoculating lactose broth and nutrient a

Consequences of shifting the chemical equilibrium, Q. What are the conseque...

Q. What are the consequences of shifting the chemical equilibrium of the formation of bicarbonate from carbon dioxide and water towards the increase of product (bicarbonate) format

A protein is normally found inside of a lipid bilayer, A protein is normall...

A protein is normally found completely within the inside of a lipid bilayer. The protein likely has: a) Mostly hydrophobic side chains, pointed outwards, with the peptide backbo

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd