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!
Polygonum Type - Monosporic Embryo Sacs
The embryo sac is formed from the chalazal megaspore in the tetrad and is eight-nucleate. The development of the embryo sac begins with elongation of the functional megaspore. Initially, the megaspore cytoplasm is non-vacuolated but later small vacuoles appear which fuse to form a large vacuole. The spindle of the nuclear division in the megaspore is oriented along the long axis of the cell. Wall is not formed after the nucleus divides.
A large central vacuole appears between the two daughter nuclei. It expands and pushes the nuclei towards the opposite poles of the cell. Both the nuclei divide to form four nuclei, two at each pole. By a further division an eight nucleate condition is reached. This is followed by cellular organisation of the embryo sac. Out of the four nuclei at the micropylar end of the sac, three organize into egg apparatus and the fourth is left free in the cytoplasm of the central cell as the upper polar nucleus. Similarly, three nuclei of the chalazal quartet form three antipodal cells; the fourth one functions as the lower polar nucleus. Eventually, the latter comes to lie close to the upper polar nucleus.
Counselling involves a process, the aim of which is to help others to help themselves by making better choices and becoming better choosers of options. The counsellor's repertoire
Why lymph is also called middle man of body
Q. False Positive ST Changes? 1) The slope of the PQ-segment can help predict the magnitude of the influence of P-wave depolarization and thus help predict which patient wou
Explain Taxonomists as Synthesisers? Your study of the earlier units of taxonomy, in particular its history must have made you aware that the field of taxonomy has changed cons
A. In order to determine the atomic number of an element we need to know the number of protons in an atom. As we know that atom is neutral we can also take the number of electro
why is a potted plant destarched before starting the experiment to investigate the factors necessary for photosynthesis
Phenylketonuria is a severe form of mental retardation caused by a recessive allele. The condition affects about 1 in 25,000 newborn babies. In a population of 250,000 people, how
How is the nervous system of nematodes organized? Where are the neural chords located in their body? Roundworms have a ganglial nervous system with an anterior neural ring sho
Soil is upper crust of earth which support land plants and animals. It is defined as addition of substances to the soil, which adversely affect physical, chemical? And biologica
How Factors Affecting Energy Expended in Physical Activity? Physical activity as we learnt earlier is the second largest component of daily energy expenditure, after BMR. Howev
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