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

Define interaction of vitamin c with pyridoxine, Define interaction of vita...

Define interaction of vitamin c with Pyridoxine? Pyridoxine is involved in glyconeogenesis through its action in transaminase reactions. Low levels of pyridoxine impair glucose

Why c4 plants are more efficient in photosynthesis, C4 plants are more effi...

C4 plants are more efficient in photosynthesis than C3 plants due to: 1. Higher leaf area 2. Presence of larger number of chloroplasts in the leaf cells 3. Presence of thi

Explain phylum cnidaria - coelenterates, Explain Phylum Cnidaria - Coelente...

Explain Phylum Cnidaria - Coelenterates? Members of the Phylum Cnidaria and one other group-Phylum Ctenophora (the comb jellies)-are the only two animal phyla that have radiall

Discuss about troponin receptor site, Skeletal muscle A. The myosin hea...

Skeletal muscle A. The myosin head is activated (energized) by the conversion of GTP (that is bound to myosin) to GDP and Pi (that are bound to myosin). B. Detachment of the

What is osmotic pressure, Q What is osmotic pressure? Osmotic pressure ...

Q What is osmotic pressure? Osmotic pressure is the pressure produced in an aqueous solution by a region of lower solute concentration upon a region of higher solute concentrat

Goal of bcc programme, The overall goal of BCC programs for diabetes mellit...

The overall goal of BCC programs for diabetes mellitus is to promote behaviors that control diabetes mellitus and prevent complications. These include: Following treatment

How to measure post repair prv/iv pressure, How to measure Post Repair Prv/...

How to measure Post Repair Prv/iv Pressure ? In the operating room, after coining of1 bypass and before removing cannulae the RV and LV pressures are measured. The pressures ar

What do you mean by taxonomist, Q. What do you mean by Taxonomist? Mode...

Q. What do you mean by Taxonomist? Modern classification systems are based on many types of evidence. A truly natural classification is obtained from analysis and harmonisation

Define the vitamin and minerals required for elderly, Define the Vitamin an...

Define the Vitamin and Minerals required for elderly? Decreased gastric secretion and intestinal motility affect the absorption and intake of nutrients especially calcium, iron

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