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 protein efficiency ratio (per), Explain the Protein Efficiency ...

Explain the Protein Efficiency Ratio (PER)? PER method was developed by Osborne, Mendel and Ferry in 1919 and is based on the growth of young rats. The diets usually contain 10

Fluids requirement in chronic diarrhoea, Q. Fluids requirement in chronic d...

Q. Fluids requirement in chronic diarrhoea? Fluids: Intake should be liberal to minimize the risk of dehydration. Remember we read about fluid management in this section before

How to investigate aortic stenosis by electrocardiogram, Q. How to investig...

Q. How to investigate aortic stenosis by Electrocardiogram? Typically left ventricular hypertrophy with strain pattern is seen in severe aortic stenosis. Total QRS amplitude in

Describe the important factors of hand washing, Describe the important fact...

Describe the important factors of Hand washing Hand washing is an important practice to follow before doing any procedure for the patient. The infection can be transferred

Define types of root canal perforations according to size, Define Types of ...

Define Types of Root Canal Perforations According to size According to size: Small perforation: ( smaller than #20 endodontic instrument ) mechanical damage to tissue is

Explain the equilibrium dialysis, Explain the Equilibrium Dialysis? Equ...

Explain the Equilibrium Dialysis? Equilibrium dialysis is a useful technique for studying the binding of a small uncharged solute species (a ligand) to a macromolecule. The mac

Nutrient cycling in tropical and temperate forests , Nutrient Cycling in Tr...

Nutrient Cycling in Tropical and Temperate Forests From this study of the nutrient cycles you must have realised the importance of the role of green plants that take up nutri

Explain ribavirin, Ribavirin (Copegus, Rebetol, and others)  Combinatio...

Ribavirin (Copegus, Rebetol, and others)  Combination treatment of HCV with peginterferon alfa and oral ribavirin has produced higher sustained response rates than peginterfero

What is harmonious ecological interaction, Q. What is inharmonious ecologic...

Q. What is inharmonious ecological interaction? The negative or Inharmonious ecological interaction is that in which at least one of the participating beings is harmed. Q.

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