Obturator - ovule, Biology

Assignment Help:

Obturator - Ovule

An obturator is an outgrowth of the placenta or funicle or integument or style near the micropyle. It is presumed to guide the pollen tube to the micropyle. This tissue is either composed of thin-walled compact tissue or it is made up of loose hairy outgrowths. The cells of the obturator at the ultra structural level, show dense cytoplasm containing a copious number of ER, dictyosomes, and vesicles. The cells of the obturator produce a surface exudate and provide mechanical and chemical guidance to the growing pollen tube.

323_Obturator.png

Figure:  Obturator in Tetragonia tetragonioides


Related Discussions:- Obturator - ovule

Explain the term- pedon and polypedon, Explain the term- pedon and polypedo...

Explain the term- pedon and polypedon The characteristics of soil do not change vertically downwards only, there are lateral variations also as soil is a three dimensional body.

Cellular features of the beings of the plant kingdom, Q. What are the major...

Q. What are the major cellular features of the beings of the plant kingdom? The typical plant cells are eukaryotic (have nucleus), photosynthetic (use light to make food) and a

Crustaceans - hormones in growth and reproduction, Crustaceans - Hormones i...

Crustaceans - Hormones in Growth and Reproduction Arthropods have a tough and frequently hard exoskeleton made up of cuticle composed of chitin and protein. The cuticle impose

.photosynthesis, what additional substance does a plant need to male amino ...

what additional substance does a plant need to male amino acids and proteins from glucose

Conclusions from the monohybrid crosses, Conclusions drawn from the Monohyb...

Conclusions drawn from the Monohybrid Crosses From the results of his monohybrid crosses, following conclusions were obtained :- 1 .       Law of Unit or Paired Factors (Po

Concept of production - ecosystems, Concept of Production - Ecosystems ...

Concept of Production - Ecosystems The ecosystems are unable to function, unless there is a constant input of energy from an external source that is sun. Solar energy enters t

Auxins - apical dominance, Auxins - Apical Dominance The role of auxin...

Auxins - Apical Dominance The role of auxins in controlling the apical dominance was shown by the experiments done by Skoog and Thimann with the broad bean plant. They removed

Phylum, classification of animal vorticella

classification of animal vorticella

In which phase mother exchanges substances to fetus, Exchange of oxygen, nu...

Exchange of oxygen, nutrients, carbon dioxide and waste products from mother to fetus takes place through diffusion across the: a) Chorionic villi (pron: core-e-on-ick villi)

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