Phytochrome - floral induction, Biology

Assignment Help:

Phytochrome - Floral Induction

Phytochrome a pigment that exists in two different inter convertible forms was discovered by Hendricks and Borthwrick et. al. and was chemically extracted and purified. Since then exact chemical nature is now established. Phytochrome has two parts the light absorbing portion (chromophore) and the large protein. Action spectra of photoperiodism, germination, and breaking of dormancy etc.-clearly establish phytochrome as the 'photomorphogenesis' pigment as its absorption spectra genuinely overlaps the action spectra of the above phenomenon. Phytochrome was found located mostly in the cell membranes. It exists in red-light absorbing form and far-red light absorbing forms. Phytochrome (R) absorbs red light and is converted into phytochrome (FR), a far-red light absorbing form.

Phytochrome Fr on exposure to far red light is reconverted to phytochrome R. Phytochrome (Fr) can also be converted to phytochrome (R) in prolonged darkness. The action of phytochrome through gene repression and depression production of flowering inducing hormones enzyme activation leading to 'floral apex' from a vegetative apex is roughly understood. But all the steps are not clear yet. Phytochrome regulated morphogenesis results for change in gene 13 transcription. Several phytochrome activated genes have been identified and isolated. One of them is PAL gene.


Related Discussions:- Phytochrome - floral induction

Explain the decolourizing agent - stain technique, Explain the Decolourizin...

Explain the Decolourizing Agent - Stain Technique? 95% ethanol is used as a decolourizing agent. It has two functions - (1) It acts as protein - dehydrating agent, and (2

+illustrate sturdy evolutionary hypothesis, Q. Why is it a sturdy evolution...

Q. Why is it a sturdy evolutionary hypothesis that although viruses are the structurally simplest beings they were not the first living beings? The fact that viruses are obliga

Is neuron a synapses onto neuron b, Is Neuron A synapses onto Neuron B ...

Is Neuron A synapses onto Neuron B Consider Neuron B in the frog central nervous system whose plasma membrane has a newly discovered ligand-gated ionotropic receptor, named the

What are the temporal factors of abnormality, What are the Temporal Factors...

What are the Temporal Factors of Abnormality Given the on going schedule of postnatal neurodevelopment, the age of the child at the time of exposure and the behaviour can have

Safety, S a f e ty, ethical and welfare considerations Development ...

S a f e ty, ethical and welfare considerations Development of transgenic organisms is proceeding in an environment of intense public debate about safety, environmental impa

Pisces, weberian oscles found in

weberian oscles found in

Explain congenital syphilis, Congenital Syphilis  A positive serologica...

Congenital Syphilis  A positive serological test for syphilis in a newborn without stigmata of syphilis may be due either to passive transfer of maternal antibodies or to prena

Structure and function of triacylglycerols , Triacylglycerols  which is als...

Triacylglycerols  which is also  known as  triglycerides or fats  consist  of  three  fatty  acid chains  esterified  to  a  glycerol  backbone.  Simple  triacylglycerols   have  t

Explain preparation and properties of modified starches, Preparation and pr...

Preparation and properties of modified starches Improved performance of starches may  be realized by physical and chemical modifications. The major physically modified starch i

Spring overturn - overturn, Spring overturn - Overturn In spring and e...

Spring overturn - Overturn In spring and early summer season the increased solar radiation melts the ice cover, which, as it attains a temperature of 4° Celsius, becomes dense

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