Central cell - synergids, Biology

Assignment Help:

Central Cell - Synergids

It is the largest cell of the embryo sac, and the mother cell of the endosperm. The enlargement of the embryo sac after the last nuclear division is mainly due to the inflation of the large central vacuole of the central cell. The vacuole in the central cell is presumably the reservoir of sugars, amino acids and inorganic salts. The nuclei of the central cell, also called the polar nuclei, are very large, and are characterized by a conspicuous nucleolus. They are present either in the centre of the cell, suspended by cytoplasmic strands, or in the cytoplasm close to the egg apparatus. In the latter case the chalazal portion of the embryo sac is occupied by a large vacuole. The two polar nuclei fuse before or during double fertilization to form the secondary nucleus.

The cytoplasm of the central cell is rich in plastids, mitochondria, numerous, dictyosomes, and ribosomes or small polysomes. This cell appears to be the centre of intensive synthetic activity in the embryo sac. The thickness of the central cell wall is variable. It is thickest in the regions in contact with the nucellus. Where the central cell touches the egg and synergids, it shows the common feature of partial wall. It becomes thinner towards the chalazal end of the egg apparatus, and finally, in the chalazal region there is no wall between the plasma membranes of the central cell and those of the egg and the synergids. The central cell is connected along with the.egg, synergids, and the antipodals through plasmodesmata connections.


Related Discussions:- Central cell - synergids

What is the inactivation of the x chromosome?what is a barr, What is the in...

What is the inactivation of the X chromosome? What is a Barr body? The Inactivation of the X chromosome is a phenomenon that occurs in women. Ever since women have two X chromo

State about the lengthy administration of test battery, State about the len...

State about the lengthy administration of test battery The lengthy administration of test battery may be unsuitable for some individuals (such as demented or psychiatric patien

What are similarities between proteins, What are some similarities between ...

What are some similarities between proteins, carbohydrates, and nucleic acids?

Why is the development of bipedalism considered, Why is the development of ...

Why is the development of bipedalism considered to be a major advancement in human evolution?

Illustrate briefly about titanium, Illustrate briefly about titanium I...

Illustrate briefly about titanium It is generally accepted that pure titanium has little cytotoxicity and it is suggested that the plaque induced inflammation may be due to cr

Define about the cellulose acetate electrophoresis (cae), Define about the ...

Define about the Cellulose acetate electrophoresis (CAE)? If the hydroxyl groups in cellulose are reacted with acetic anhydride, cellulose is acetylated to form the raw materia

Grouping of stem cells-totipotent scs, Grouping of Stem Cells: The rang...

Grouping of Stem Cells: The range of differentiation “Potency” is an important property of Stem cells & serves as the basis for classifying cells as : Totipotent SCs -capa

Illustrate the thin and think filaments in the muscle fiber, Illustrate the...

Illustrate the thin and think filaments in the muscle fiber A healthy skeletal muscle fiber is isolated and has no external forces on it.  It has normal intracellular levels of

Plant nutrition, what is usually regarded as evidence that photosynthesis h...

what is usually regarded as evidence that photosynthesis has occurred in a plant?

How does vitamin c act in the body, How does vitamin C act in the body? Wha...

How does vitamin C act in the body? What is the harm caused by insufficiency of vitamin C? Why was this deficiency also known as "sailors' disease"? Vitamin C, or ascorbic acid

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