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

Structural differences between roots and shoots, What are the structural di...

What are the structural differences between roots and shoots? What structures are unique to each?

The cerebrum, The cerebrum is clearly the most interesting part of the brai...

The cerebrum is clearly the most interesting part of the brain from the point of view of cognitive neuroscience. The cerebrum consists of highly symmetrical left and right hemisphe

Absorption of photic energy for photosynthesis, Q. What is the main molecul...

Q. What is the main molecule responsible for the absorption of photic energy for photosynthesis? And where is that molecule located in photosynthetic cells? The chlorophyll mol

Explain advantages of periodontal ligament, Explain periodontal ligament ...

Explain periodontal ligament The absence of the periodontal ligament and the presence of osseointegration instead of the gomphosis joint leads to the difference in movement un

Study of tonana larva, Study of tonana larva Tornaria larva is typical...

Study of tonana larva Tornaria larva is typical in the life-history of hemichordates. Examine the permanent slide and note the following features: I. The tornaria larva usu

Are nematodes exclusively parasites, Are nematodes exclusively parasites? ...

Are nematodes exclusively parasites? There are parasitic roundworms, containing parasites of plants, but there are also free-living nematodes.

Explain long-term risk estimation, Explain Long-term Risk Estimation ? ...

Explain Long-term Risk Estimation ? Many studies have examined long-term risks associated with risk factors using traditional epidemiological methods. Framingha investigators

Difference between unconditioned & conditioned reflex action, Difference be...

Difference between unconditioned and conditioned reflex action- S.NO .   1. UNCONDITIONED   It is inborn CONDITIONED

Explain the storage of vitamin a, Explain the Storage of vitamin A? The...

Explain the Storage of vitamin A? The primary organ for storage of vitamin A is the liver. Reserves are found in the stellate cells, as mentioned above. The average liver weigh

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