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

How does the swim bladder of fishes work, How does the swim bladder of fish...

How does the swim bladder of fishes work allowing fishes to control their depth under water? From Hydrostatics it is called that an object does not sink if its density is equal

Describe the complete transposition of great arteries, Describe the Complet...

Describe the Complete transposition of great arteries ? Lethal, relatively frequent malformation. Without treatment, it results in 30 per cent mortality within the first week o

How many ml should the nurse administer, The doctor writes an order for 125...

The doctor writes an order for 125 mg of a medication. The label on the vial states "50 mg per ml". How many ml should the nurse administer?

What is meant by unsaturation or saturation of oils and fats, Q. What is me...

Q. What is meant by unsaturation or saturation of oils and fats? When it is said that a triglyceride is saturated it means that in its molecule the carbon chain is bound in its

Trace minerals-chromium, Chromium Chromium functions as a component of ...

Chromium Chromium functions as a component of the glucose tolerance factor, which serves to potentiate the action of insulin. Adding low concentrations (0.02 to 1.0 mg/kg) of c

Explain an open circulatory system, Why, even though they have an open circ...

Why, even though they have an open circulatory system, can flying insects like flies beat their wings with great speed? In insects the circulatory system is open but this syste

The first carbon having 2 h atoms, Given a polymer backbone of H-C-C with t...

Given a polymer backbone of H-C-C with the first carbon having 2 H atoms attached and the 2nd carbon with 3 atoms attached, a bond with a water molecule attaches to the left H atom

Conditions necessary for outbreak of botulism, Q. Conditions Necessary for ...

Q. Conditions Necessary for outbreak of botulism? The following conditions are necessary for an outbreak of botulism: 1. Presence of spores of C. botulinum of type A, B o

Define vitamins b12 deficiency in vegans, Define Vitamins B 12 Deficiency ...

Define Vitamins B 12 Deficiency in Vegans? Because plants do not synthesize vitamin B 12 , individuals who consume diets completely free of animal products (vegan diets) are a

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