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

Define about the pseudosquint, Define about the Pseudosquint (Pseudo-false...

Define about the Pseudosquint (Pseudo-false) Pseudosquint is the condition when despite the visual axis being parallel, there , appears to be a squint. Pseudosquint can be conv

Explain about the commercial sterility, Explain about the Commercial Steril...

Explain about the Commercial Sterility? It is important to remember that bacterial destruction is a logarithmic function, complete destruction not probable to make food commerc

Explain urine urea nitrogen - nutrition during stress, Explain Urine Urea N...

Explain Urine Urea Nitrogen - Nutrition during Stress? 5 gm/24 hrs. = No stress 5 to 10 gm/24 hr = mild hyper-metabolism or level 1 stress 10 to 15 gml24 hrs = moderat

What does fungus looks like, Q. What does this fungus looks like? Ans...

Q. What does this fungus looks like? Ans. The important characteristic features of aflatoxicosis are jaundice, cirrhosis. Long term exposure to aflatoxins could lead to

What mechanism of regulation utilized in maintaining, What mechanism of reg...

What mechanism of regulation is utilized in maintaining homeostatic balance of sugar?

Do all molecules of dna have the same amounts, Q. Do all molecules of DNA h...

Q. Do all molecules of DNA have the same amounts of nitrogenous bases? Number and sequence of nitrogenous bases in DNA molecule are key elements in variations which are found i

Supplementation to prevention of iron deficiency anaemia, Define Supplement...

Define Supplementation to prevention of iron deficiency anaemia? Supplementation with low doses of iron is necessary to prevent anaemia in particular groups of people. Fortifie

Determine the prosthodontic considerations, Prosthodontic considerations ...

Prosthodontic considerations In order to achieve good results, understated features should always be examinated. 1. Smile Line: A high smile line increases the esthetic

State the term - antecedent and consequence control, Antecedent and consequ...

Antecedent and consequence control Therapy and consultation cannot be effective unless the behaviours to be changed are understood within a particular context. The process of u

Cyanotic congenital heart disease, Cyanotic Congenital Heart Disease   ...

Cyanotic Congenital Heart Disease   So far we have discussed the acyanotic congenital heart disease. Now we shall discuss some of  the main cyanotic congenital heart diseases.

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