Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
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.
Platinum color in foxes is produced by heterozygous genotype Ss, and silver foxes are the genotype SS. The genotype ss is lethal, and the fox dies in early embryonic development. I
case study haematology
how many chromosomes in human
What is Demographic Transition? The whole process of change with regard to population size and characteristics is called demographic transition. In order to understand this ter
describe the discovery of new fossil evidence for evolution
Define about Skeletal system Skeletal system provides framework to the body; supports the soft tissues; protects delicate organs. The skeletal system is made up of bones an
Explain about the Adipose tissue - energy balance? At this point, it will not be irrelevant to consider how exactly an increase in the fat depot takes place. For understanding
Atopic dermatitis is an inflammatory skin disease. This disease is observed frequently in young children. There will be skin eruptions.
What is Active Transport--Secretion This method is now a well accepted process of aqueous formation. The rate of aqueous humour formation depends on the rate of active solute
Electron Transport Inhibitors Several compounds, including specific drugs, chemicals and antibiotics have been known to inhibit the electron transfer reactions at specific
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd