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

Embryonic membranes, EMBRYONI C MEMBRANES - Such animals are called a...

EMBRYONI C MEMBRANES - Such animals are called amniota. Embronic membranes are of 4 types - (i) Yolk sac - It is formed below the embryo. It contains fluid (no yolk

Respiration in cockroach, what is the chemical reaction of respiration in c...

what is the chemical reaction of respiration in cockroach?

What are the main novelties presented by fishes, Comparing to cyclostomes (...

Comparing to cyclostomes (primitive vertebrates) what are the main novelties presented by fishes? Compared to cyclostomes, evolutionary novelties shown by fishes are: pectoral

Methods of solid waste disposal, Commonly adapted different disposal method...

Commonly adapted different disposal methods by the municipal corporations are: (a)   Open dumping (b)   Land filling (c)    Sanitary land filling pyrolysis (d)   Incine

Mouth bacteria and tooth decay, What is the connection among this substance...

What is the connection among this substance, mouth bacteria and tooth decay? Mouth bacteria use sugar for their metabolism and produce acids as a waste-product. The acids diss

Cell, The scientist who described cells as “many little boxes” was

The scientist who described cells as “many little boxes” was

Indications for surgery-mitral valve disease, Indications for Surgery :  T...

Indications for Surgery :  The normal mitral valve area is 4-5 cm 2 . Usually symptoms appear when the valve area has become less than 2.5 cm2. Symptoms are present at rest when t

What is the determination of vitamin B1, What is the Determination of vitam...

What is the Determination of vitamin B 1 Vitamin B 1 is determined by chemical method and microbiological assay. In the chemical method, vitamin B 1 is oxidized in alkaline

Parts of a seed , Parts of a Seed Seed is attached to the fruit by a ...

Parts of a Seed Seed is attached to the fruit by a stalk, the funiculus (funicle). The prolongation of the funiculus running along the seed and terminating at the chalaza is

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