Morphogenesis and totipotency, Biology

Assignment Help:

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.


Related Discussions:- Morphogenesis and totipotency

Introduction of quality attributes of food, Q. Introduction of Quality Attr...

Q. Introduction of Quality Attributes of Food? Seasonal fruits and vegetables are grown in plenty, and are available in their respective seasons in abundance. While choosing th

Calculate the insulin bolus and drip rate , Mrs. M is a 35-year-old Hispani...

Mrs. M is a 35-year-old Hispanic female with no known past medical history; does not have a primary care provider (PCP). She presents to the emergency department with the following

Which is the kind of nitrogen waste birds produce, Q Which is the kind of n...

Q Which is the kind of nitrogen waste birds produce? Why does this feature, besides being an adaptation to the terrestrial environment, also mean an adaptation to flight? Birds

Nutrition and health, Nutrition and Health The effects of the socio-ec...

Nutrition and Health The effects of the socio-economic and environmental factors in which one is constrained to live will manifest in terms of the nutritional and health statu

What is intercellular communication explain briefly, What is Intercellular ...

What is Intercellular Communication explain briefly? Both plant and animal cells have developed means of communication between cells. In animals, specialized areas of the cell

Of what importance are lactic acid fermentation to the cell, Of what import...

Of what importance are lactic acid fermentation and alcoholic fermentation to the cells that use these pathways? These pathways regenerate NAD, which the cells can use to keep

What kind of eye defect can give rise to short-sightedness, What kind of ey...

What kind of eye defect can give rise to short-sightedness? Long eyeballs, large eyeballs, too powerful a lens or a combination of these defects can give increase to short-sigh

Which are the brain regions associated with memory, Which are the brain reg...

Which are the brain regions associated with memory? According to researchers some of the main regions of the nervous system associated with the memory phenomenon are the hippoc

What do you mean by nervous system, Q. What do you mean by Nervous System? ...

Q. What do you mean by Nervous System? Structural Organization:   CNS + PNS Functional Organization:   only concerned with PNS Sensory (Afferent) ->  CNS Motor (Effe

Explain the importance of human genome project, Question 1: Explain the...

Question 1: Explain the importance of Human Genome Project in Research and list the different methods available for Gene sequencing Mention the importance of Human Genome

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd