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.
describe and compare reproduction in all the kingdoms except kingdom animalia
History of evolution? Evolution is usually defined as "change over time." In spite of the incredible diversity of life found on Earth, many fundamental characteristics are shar
What are the valves of the venous system? What is their function? The valves of the venous system are structures within the veins that permit blood to flow only in the normal w
Define Reagents for Estimation of Calcium Using EDTA Titrimetric Method? 1. Buffer solution: Dissolve 16.9 g NH 4 CI in 143 ml NH 4 OH. To this add 50 ml of solution containing
EXCRETION IN HUMAN -
Explain the Procedure for Preparation of Bacterial Smear? Start the exercise by following the steps enumerated herewith. (1) Take properly washed and dried glass slides for
Define Mechanism of Rotary Instrument Fracture - Cyclic Fatigue Occurs unexpectedly and without any visible signs of plastic deformation o An instrument rotating freely in a cu
Workgroup A Workgroup is a group of people who are working together on the same project. The members of such a group are usually (not always) located in close physical proximi
Q. Treatment and Management of Hypertension? The first choice of treatment and management of primary hypertension is through behaviour modifications pertaining to food choices
Explain about Urinary system Urinary system provides us with the service of disposing the waste products carried by blood. This function is also known as excretion.
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