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!
Morphogenesis and Totipotency
A chlamydomonas mother cell gives rise to two daughter cells by a simple division. But a leaf cell cannot give rise to a new plant except in cases like Bryophyllum or Kalanchoe. What makes a daughter cell of a zygote to loose the 'potential' to develop into a whole plant? Or if all the daughter cells possess this potential- i.e. if they are totipotent-why it does not express? These questions troubled Haberlandt-hundred years ago. He postulated that any living plant cell should be able to grow into a full plant. He experimented with mesophyll cells at a time when tissue culture had not been unheard for. His experiments failed because we now know that isolated mesophyll cells are not really easy to grow to unleash their morphogenetic potential.
F.C. Steward-who took up this work sixty years later-successfully cultured whole carrot plants from carrot phloem parenchyma cell. He published the papers in the American Journal of Botany in the late 1950's. Steward and his coworkers took 2 mg. tissues of secondary phloem of carrot roots and grew them in special flasks with nipples or tubes called tumble tubes. The medium was whites' medium with coconut water. These tubes/flasks were mounted on a wheel that was rotated on a shaft at the rate of 1 r.p.m. So that the pieces were alternately aerated and bathed in the liquid medium. There was an enormous increase in size of the explants. A callus ensued. A few peripheral cells slaughtered off into the medium and started dividing and gave rise to clumps,-occasionally with roots these could be transferred to semi-solid medium in (still) tubes. Shoots arose opposite the roots to yield full plants. Subsequently other parts were also used to, demonstrate cellular totipotency.
Modern Biology Increasing advancement in biotechnology has brought about a veritable explosion of Biological knowledge since early 1950s.This vast modern biological information
#questiocan you help in a biology question?.
Q. What is the role of the ozone layer for living beings? The Ozone, O3, is a gas of the atmosphere that filters ultraviolet radiation from the sun disallowing most of that rad
Q Which are the organs and characteristics of the digestive system of earthworms related to the kind of diet of these animals? Small organisms ingested together with soil parti
what cause to hypertention?
Acetylcholine is the chemical released at neuromuscular junctions which binds to receptors on the surface of the plasma membrane of the muscle cells, creating an electrical impuls
Explain the Virtual Dissection of the Rat in multimedia tutorials? This animation will teach you about basic mammalian anatomy. The major organ systems in a rat are very simila
What is Sodium Bicarbonate? The administration of bicarbonate may be considered if the pH remains below 7.1 or if hyperkalemia or tricyclic antidepressant overdose is suspected
Q. What is quaternary structure of a protein? Do all proteins have quaternary structure? The quaternary protein structure is the spatial conformation due to interactions among
Which is the part of the human visual system where the receptors that sense light, i.e., the photoreceptor cells, are located? How do those cells work? The photoreceptor cells
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: +1-415-670-9521
Phone: +1-415-670-9521
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd