Phytochrome - floral induction, Biology

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.

Posted Date: 1/24/2013 1:19:38 AM | Location : United States







Related Discussions:- Phytochrome - floral induction, Assignment Help, Ask Question on Phytochrome - floral induction, Get Answer, Expert's Help, Phytochrome - floral induction Discussions

Write discussion on Phytochrome - floral induction
Your posts are moderated
Related Questions
A question is flashed on a screen in the left visual world of right-handed person Z. Person Z is a healthy individual with an normal nervous system.  Person Z has a patch over Z's

Explain the inferior dental nerve The inferior dental nerve in some cases may divide into two or three rami that occupy separate canals as the nerve travels in the mandible to

Q. What is the constitution of the cartilaginous matrix? The cartilaginous matrix is made of generally collagen type II, collagen fibers, and of proteoglycans, proteins associa

Food Web - Ecosystem A plant may serve as a food source for many herbivores simultaneously, e.g. grass plants can support deer, cow, grasshopper or rabbit. Similarly a herbivo

Looking at what the academic world is publishing, microarray research is actually hot right now, and people haven't quite figured out what the best way is (some might argue if we s

Effects on plants of Air pollutants SO 2 , O 3 and NO 2 are strong oxidants and can bring about significant changes in plant cell chemistry. The general effects of pollutant

What are the main cellular features of fungi? There are unicellular and pluricellular fungi. All fungi are eukaryotes and heterotrophs. Fungi have cells with cell wall made

Effects on Ecosystem - Air pollutants The effects of pollutants on ecosystem become visible after a long period of exposure. In highly industrialised countries the vegetation


Reasons for Uneven Distribution of Power The causes for uneven distribution of the power of regeneration among animals are not noticeably known. From a survey of the regenerat