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

Retain the tooth there are two ways-endodontics principles, Once the decisi...

Once the decision has been made to retain the tooth there are two ways for ttt: •     Non surgical retreatment :             -  guided access to apex via coronal access

Describe the positive end expiratory pressure, Describe the Positive End Ex...

Describe the Positive End Expiratory Pressure (PEEP)? A positive pressure may be applied at the end of the expiratory phase during mechanical ventilation, instead of allowing t

Explain the pipettes - food microbiology, Explain the Pipettes - Food Micro...

Explain the Pipettes - Food Microbiology? Sterile glass pipettes or disposable pipettes can be used for transferring the known volume of liquid or culture aseptically. Steriliz

How many different genotypes can the individual present, Considering a pair...

Considering a pair of homologous chromosomes containing a gene having two different alleles how many different genotypes can the individual present? If a gene of a diploid spec

Explain the principle of development, Explain the Principle of Development ...

Explain the Principle of Development The final guiding principle is that assessment involves the measure of change, or development, across multiple levels of analysis. Developm

Fundamental aspects of protein structure, Can someone describe the fundamen...

Can someone describe the fundamental aspects of protein structure? I'm already familiar with the amino acid structure, I just don't have a clear conceptual understanding of protein

What are Modes of Nutrition, What is Nutrition? Explain types of nutrition?...

What is Nutrition? Explain types of nutrition? Nutrition - Taking Nutrients from environment Nutrients - Substances which are needed for the sources of chemical potential en

How water content influence the rs content, How Water content Influence the...

How Water content Influence the RS content? The yield of RS formed in heat-moisture treatment is closely related to water content, which may be an inherent component of food or

Explain the minimum requirement of nutritional needs, Explain the Minimum R...

Explain the Minimum Requirement of nutritional needs? Minimum nutrient requirement is defined as the 'lowest amount of the nutrient ji-om the diet that will prevent clinically

Explain atrial pressure, Q. Explain Atrial Pressure? The RA pressure wa...

Q. Explain Atrial Pressure? The RA pressure wave form has three positive deflections - "a", "c", and "v" waves. The "a" wave is due to atrial systole and follows the P-wave on

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