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

Vitreous expansion-contraction in physio-chemical property, Illustrates the...

Illustrates the vitreous expansion and contraction in the physio-chemical property? Vitreous Expansion and Contraction The positive charge in Na ions, NaCl molecule and

Techniques of plant tissue culture, Techniques of Plant Tissue Culture ...

Techniques of Plant Tissue Culture A standard tissue culture laboratory should provide facilities for washing and storage of glass ware, preparation and storage of nutrient

Describe the kinds of muscle tissues, Q. What are the kinds of muscle tissu...

Q. What are the kinds of muscle tissues? What are the morphological features that differentiate those types? There are three kinds of muscle tissue: the cardiac striated muscle

Restricted lung diseases, Restricted Lung Diseases Restricted lung dis...

Restricted Lung Diseases Restricted lung disease are classified into the following: Parenchymal inflammation. This can be due to infection e.g. pneumonia acute bronchi

Explain pea plants in genetics, Explain pea plants in genetics? Pea Pl...

Explain pea plants in genetics? Pea Plants :   In pea plants, sperm are located in the pollen grains produced by the anthers of the flower. Eggs are formed in ovules, structur

Why is this area more vulnerable to damage than others, A small family was ...

A small family was traveling in the car when a minor accident happened. The children in the back seats were wearing lap belts, but still sustained numerous bruises about the abdome

Elaboration of yolk- reproduction, Normal 0 false false fal...

Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4

Diet for cardiac patients, Diet Continue diet as prescribed at hospita...

Diet Continue diet as prescribed at hospital. Some may continue fluid and salt restriction, some may have to restrict iron and Vitamin K rich food stuff. The patient needs t

Describe how potassium is essential, How potassium is essential for the fol...

How potassium is essential for the following physiological functions It is vital for photosynthesis. When K + ion is deficient, photosynthesis declines and respiration incr

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