Ovule, Biology

Assignment Help:

Ovule

The ovule, also known as the megasporangium is the forerunner of the seed. It consists of a central mound of tissue called the nucellus, which is enveloped by one or two coverings - the integuments. An ovule ready for fertilization consists of nucellar tissue enveloped almost completely by integument(s), leaving a small pore or opening at the apical end.

This opening, called micropyle is the main passage for the entry of the pollen tube into the ovule. This end of the ovule is generally referred to as the micropylar pole and the opposite pole where funiculus is attached is called the chalazal pole. The ovule is attached to the placenta through a stalk-like structure the funiculus. In the nucellus is present the female gametophyte which is commonly referred to as the embryo sac.

 


Related Discussions:- Ovule

What is the concept of lophophore, What is the concept of Lophophore? A...

What is the concept of Lophophore? A unique double ring of hollow ciliated tentacles that surround the oral opening in some animal phyla. There is some debate as to whether the

Determine the types of symbols used in soil horizons, Determine the types o...

Determine the types of symbols used in Soil Horizons  Three kinds of symbols are used in various combinations to designate horizons. These are capital letters, lower case lett

What is meant by the law of use and disuse, What is meant by the law of use...

What is meant by the law of use and disuse and by the law of the transmission of acquired characteristics? As per to the law of use and disuse the characteristics of a body var

Define mechanism for copper absorption, Define Mechanism for Copper Absorpt...

Define Mechanism for Copper Absorption? As in the case of other minerals, copper absorption appears to occur by two mechanisms: i) Saturable active mechanism, which operates

Uptake of iron by enterocytes - non-haem iron absorption, Define Uptake of ...

Define Uptake of iron by enterocytes - Non Haem Iron Absorption? Ferrous iron traverses the brush border of the intestine better than the ferric iron. The mechanism of absorpti

Interkinesis, There is no Interphase preceding second meiotic division. ...

There is no Interphase preceding second meiotic division. There is a brief intervening period called Interkinesis During this period there may be synthesis of some reserve fo

What are the four types of weak bonds, What are the four types of weak bond...

What are the four types of weak bonds, and how do they differ from each other and from covalent bonds? When you eat a salad with lettuce, croutons, hard-boiled egg, bacon bits,

Explain the interaction of vitamin a with proteins, Explain the interaction...

Explain the interaction of vitamin a with Proteins? Proteins: The protein status of an individual influences vitamin A status and transport because an inadequate protein intake

Define nutrition screening initiative (nsi), Define Nutrition Screening Ini...

Define Nutrition Screening Initiative (NSI)? (NSI) tries to identify basic risk factors - inappropriate food intake, poverty, social isolation, disability, acute / chronic dise

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