Biochemical changes, Biology

Assignment Help:

Biochemical Changes

Many workers have tried to follow the biochemical changes that precede flowering and result in meristems which give rise to flowers instead of vegetative structures. In Pharbitis, which is a short-day plant and requires only one dark period for flowering it was found that soon after the dark period, the flowering stimulus begins to move out of the leaves. In this experiment, the plant was given inductive conditions and after specific time intervals, biochemical changes were measured in meristems. An increase in metabolic activity around 40th hour at the floral apex was manifested by an increase in the level of RNA, proteins and ribosomes. Electron microscopic observations also revealed extensive formation of endoplasmic reticulum.

These activities were followed by an increase in DNA synthesis and mitotic activity. At about 88th hour after floral induction, the rate of cell division increased at apical and axillary meristems and the increase in cell division was noticed particularly in the central zone and peripheral zones of apical meristems. Such experiments have also been done in other plants. However, it has not been possible yet to identify which of the RNA or proteins are responsible for the onset of flowering. With the application of newer techniques it has been possible to suggest that there are some specific flowering genes which get switch on after receiving specific light-dark cycle. Although we do not know the products of all these genes, some of them have been shown to code for proteins which regulate transcription.


Related Discussions:- Biochemical changes

Define the role of vitamin d in the immune system, Define the Role of Vitam...

Define the Role of Vitamin D in the immune system? Immune responses that are, mediated by T-cells can be inhibited by tile large doses of calcitriol i.e. 1, 25 dihydroxycholec

Distinguish among the terms stimulus and sensation, Q. Distinguish among th...

Q. Distinguish among the terms stimulus, sensation, and perception? A stimulus is an energy source (chemical, light wave, pressure etc.) which activates a receptor cell (specia

What are the main functions of the cytoskeleton, Q. What are the main funct...

Q. What are the main functions of the cytoskeleton? As the name indicates, the cytoskeleton is accountable for the support of the normal shape of the cell it also acts as a fac

Define the process of small intestine during digestion, Q. What is the subs...

Q. What is the substance produced in the liver that acts in the small intestine during digestion? How does that substance act in the digestive process? Bile is an emulsifier li

Heart in reptiles, Reptiles  Heart is incomplete 4 chambered, ventri...

Reptiles  Heart is incomplete 4 chambered, ventricles are not divided completely 2 auricels & 2 ventricles. Sinus venosus present, Truncus artiorsus absent [In lizzard fo

What do you mean by binomial system in binomial nomenclature, Q. What do yo...

Q. What do you mean by Binomial system in binomial nomenclature? In the previous sections we have outlined the concepts of binomial nomenclature at International level and the

Membrane protein purification and reconstitution, The first step of the pur...

The first step of the purification of an integral membrane protein is to disrupt its interactions with other integral proteins and the lipids in the membrane.  This is commonly ach

Explain about the infantile beriberi, Explain about the Infantile beriberi?...

Explain about the Infantile beriberi? Infantile beriberi is commonly seen in many South-East Asian countries where the diets consist mostly of "polished rice" and are deficient

Explain phylum tracheophyta, Phylum Tracheophyta Tracheophytes mean vas...

Phylum Tracheophyta Tracheophytes mean vascular plants. Tracheophyta includes ferns, the gymnosperms and the flowering plants. They have appeared some 400 million years ago, an

Marine extremophiles, how to make a assignment on recent research on marine...

how to make a assignment on recent research on marine microbiology

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