Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
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.
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.
In the living condition (found in sea) you would be able to observe the following features in radiolarians: The cytoplasm is divided by a perforated and chitinous metnbrane into
Class of Crustacea - Branchiopoda These are small fresh water crustaceans. The trunk appendages are flattened and leaf like and are helpful for locomotion also respiration he
Q. Briefly explain about semantides? The information carrying molecules in plants are called semantides, and they have been recognised to be 3 kinds; deoxyribonucleic acid or D
Does mitosis properly occur before or after the interphase? Is it a mere "point of view" issue? Mitosis must be considered a succeeding phase after interphase since this
Coccidioidomycosis Coccidioidomycosis is a soil-borne infection of pet, domestic, wild animals and man. The disease is caused by Coccidioides immitis, a dimorphic fungus wh
Write an essay on cytological approach in taxonomy.
Slight or no Metamorphosis In primitive wingless insects (Apterygota) such as spring tails, silver fish etc. and in secondarily apterous insects the young ones which hatch fr
Explain the Food Irradiation - method of food preservation? Food irradiation is another sterilizing technique in which the foods are bombarded by high-energy rays called gamma
Determine the use of OPG An OPG is used to see the possibility for an anterior loop which is found to extend about 1-3 mm anterior to the mental foramen in about 12 per cent
Nature and Structure of Community Every place on earth -grasslands, forests, and ponds, edge of the river or sea is shared by many coexisting organisms. Plants, animals and mi
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd