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

What is oral hygiene, What is Oral Hygiene  An index can be used to eva...

What is Oral Hygiene  An index can be used to evaluate the oral hygiene level in the patient e.g. Oral hygiene Index (Green and vermilion) or Plaque index (Silness and Loe). An

Explain the term protoderm, Explain the term Protoderm? The protoderm ...

Explain the term Protoderm? The protoderm is one of the so-called "primary tissues" because it is formed first during germination and subsequent plant growth. The protoderm g

Define lamivudine, Lamivudine This oral antiretroviral nucleoside analo...

Lamivudine This oral antiretroviral nucleoside analog used to treat HIV is also FDA-approved for treatment of chronic HBV infection. A trial in Asian patients with chronic HBV

Phospholipids - conjugated lipids, PHOSPHOLIPIDS Most abundant lipid...

PHOSPHOLIPIDS Most abundant lipid present in cell membrane, also called membrane lipid. It is made up of lipid & phosphoric acid. The basic phospholipid is phosphat

Find the magnitude and direction of the net electric force, Three point cha...

Three point charges are located at the corners of an equilateral triangle as in the figure below. Find the magnitude and direction of the net electric force on the 1.40 µC charge.

What are the consequences of iodine deficiency disorders, What are the cons...

What are the consequences of iodine deficiency disorders? As discussed earlier under signs and symptoms, the consequences of IDD include: mental retardation, other defects in t

Define national programmes targeting infants and preschooler, Explain Natio...

Explain National Programmes Targeting Infants and Preschoolers? Infants and preschoolers are the vulnerable sections of the society. To give them due  coverage, some national p

Explain the work of john ray in animal taxonomy, Explain the Work of John R...

Explain the Work of John Ray in Animal Taxonomy? The first important work on both animal and plants was initiated by John Ray (1627-1705). He followed Aristotle and divided ani

Explain rectangular full mucoperiosteal flaps, Explain Rectangular Full Muc...

Explain Rectangular Full Mucoperiosteal Flaps - Endodontic Surgery      a. Releasing and relaxing "vertical" incisions, with the Horizontal incision, b. Causes re

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