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!
Egg - Synergids
The three cells of the egg apparatus are arranged in triangular fashion with the egg sharing a common wall with the two synergids and the central cell. In the egg the wall is thicker at the micropylar end and is absent at the chalazal end. At this end the lateral walls of the egg cell appear to join the central cell wall. The egg cell wall is traversed by plasmodesmata on the sides of the two synergids and the central cell but not at its outer face. The egg cell becomes highly polarized early in its development. Polarity is expressed by the aggregation of cytoplasmic elements at the chalazal end of the cell. The micropylar end of the cell is occupied by a large vacuole. Thus, the distribution of the vacuole and cytoplasm in the egg cell is just the opposite of that in the synergids.
The ultra structure of the egg cytoplasm indicates that it is inactive. The mitochondria show only a few cristae. But for Zea mays, dictyosomes are either absent (Epidendrum) or are only a few in numbers. Where present, the dictyosomes exhibit an inactive state. Plastids are present in the egg; they often contain a striking difference from the male gametes. The egg cytoplasm is rich in ribosomes. In Plumbago capensis where the embryo sac lacks synergids. However many finger- like wall projections arise at the micropylar end of the egg cell. They resemble the filiform apparatus of the synergids. In this plant the egg cell seems to have taken over the role of synergids in addition to its own gametic function.
Do the arteries that carry blood from the heart to the lungs have arterial or venous blood? What happens to the blood when it passes through the lungs? Arteries of the pulmonar
What are Cytokines? Cytokines are polypeptides, which influence the proliferation, differentiation, metabolism and activation of cells. There are three areas in cancer that hav
What is an open circulatory system? Open circulatory system is the one in which blood does not circulate only in blood vessels but it also falls in cavities that irrigate tissu
Platyhelminthes - Nervous Systems Among Platyhelminthes, you will observe that turbellarians have a brain and three to five pairs of longitudinal nerve cords extending from th
Q. Are organic solvents like benzene and ether non-polar or polar substances? the ethers and Benzene are molecules without electrically charged portions and thus they are non-p
how can i read role od fungi as saprophyte?
PROTEINS Protein was discovered by Mulder. Berzilius gave the catalytic concept & gave the word protein, which means first rank. Protein holds the 1st place in
What is the mode of nutrition in fish,human,amoeba,scorpian & toad ?
what''s you''re name
Explain the term - Neurochemical Manipulations Neurochemical and immunological methods have been used to identify groups of neurons in the central nervous system that use speci
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