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

Acid rain, what are the two main pollutants that contribute to acid rain

what are the two main pollutants that contribute to acid rain

Horizontal chart - organization chart, Horizontal Chart: Horizontal ch...

Horizontal Chart: Horizontal chart which read from left to right are occasionally used. The pyramid lies horizontally instead of standing in the vertical position. The line of

Pollen tube growth, Pollen Tube Growth There are significant differen...

Pollen Tube Growth There are significant differences in the fine structure of the tips of pollen tubes in compatible and incompatible pistils such as Lilium. Tubes growing in

Hormones secreted by pituitary gland, (a) Hormones of the Anterior lobe - ...

(a) Hormones of the Anterior lobe - The anteriorIobe of the pituitary gland secretes the following hormones, most of them are trophic hormones. (i ) Somatotropic hormone o

The halstead-reitan neuropsychological battery, The halstead-reitan neurops...

The halstead-reitan neuropsychological battery The beginnings of the battery can be traced to the special laboratory established by Halstead in 1935 for the study of neurosurgi

Explain the inoculating loops and needles, Explain the Inoculating Loops an...

Explain the Inoculating Loops and Needles? These are most commonly used tools for inoculation. The inoculating loop consists of insulating handle at the end of which inoculatin

Types of stem cells-pulp tissue revascularization, Embryonic stem cells: c...

Embryonic stem cells: can differentiate into all cell types of the specialized embryonic tissues when given sufficient and necessary stimulation for a specific cell type, e.g. Plu

Principles governing cleavage, Principles Governing Cleavage a) The n...

Principles Governing Cleavage a) The nucleus and mitotic achromatic figure tend to occupy the centre of active cytoplasmic density of the dividing cells, e.g., in isolecithal

Coniferous forests and taiga, As you travel south from the tundra you will ...

As you travel south from the tundra you will enter the circumpolar belt of coniferous forests which stretches across North America to Eurasia, this region is called taiga, a world

Elaborate angiography, Which term is used to describe the process whereby a...

Which term is used to describe the process whereby a catheter is inserted into an individual's heart, a radio-opaque medium is injected & x-ray images are made. Procedure is use

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