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.
Name three useful products that can be obtained by genetic engineering. Useful products of genetic engineering are:- A) chymosin, B) Alpha-anti-trypsin, C) hepatitis
Differentiate soil horizons and mong the soil groups To make precise differentiation among soil horizons and among the soil groups, the field data on soil morphology are suppor
Define Protein Requirements during Sepsis? Adequate amount of protein is required by these patients to improve immunity against infections, promote recovery, spare lean body ma
Vital Dye Staining In this type of method, a piece of agar or cellophane soaked in the solution of a vital dye (Neutral Red, Nile Blue Sulphate, and Bismarck Brown etc.) is a
How does the pancreatic juice resume the digestion of carbohydrates? What is the involved enzyme? Carbohydrate digestion starts with the action of the salivary amylase (ptyalin
Pulse Oximetry: Procedure: Pulse Oximetry is a safe and simple method of assessing oxygenation. An advantage is that this method is noninvasive and continuous. Previously,
Drowning: Drowning is a cause of accidental death in children Accidental drowning may occur because children do not have adequate protective supervision. It may be defined
Aid-giving behaviour between genetically related individuals in animal groups is often observed in nature. This aid-giving behaviour can evolve when the advantages of helping relat
a) What are the advantages of human milk over cows' milk for feeding babies? b) Apart from the composition of the milk, what are the other advantages of breast- feeding?
Define Steps To determine thermal resistance of a microorganism? Most food components and microorganisms obey first order reaction kinetics, which means that the destruction ra
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