Biochemical changes, Biology

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.

Posted Date: 1/17/2013 7:26:22 AM | Location : United States







Related Discussions:- Biochemical changes, Assignment Help, Ask Question on Biochemical changes, Get Answer, Expert's Help, Biochemical changes Discussions

Write discussion on Biochemical changes
Your posts are moderated
Related Questions

Q. How execute the two complementary nucleotide chains of the DNA facilitate the replication process of the molecule? The fact that DNA molecule is made of two polynucleotide c

Explain Beef Extract and Yeast Extract These are aqueous extracts of lean beef and brewer's yeast, respectively. Beef extract provides amino acids, peptides, nucleotides, organ

Role of Chemical Factors in Controlling Apical Dominance There were indications about the existence of plant hormones in the last part of 19th century. The plant hormones had

Biota of the Neritic Oceanic Zone This zone constitutes 75 per cent of the total oceanic area and is relatively rich in species and high in productivity owing to factors such

Cellulose Cellulose is found in plants as microfibrils (2-20 nm diameter and 100-40,000 nm long). These form the structurally strong framework in the cell walls. Cellulose is


Explain what is Correction of Hypovolemia ? Intravenous fluids should be given to correct hypovolemia and optimize preload to the heart. This is particularly important in sept

Neural Circuits The simple all are none activities of a single neuron can hardly provide the adaptability needed for the constant changes faced by the organism in its internal

Classification of Enzymes It has been a long tradition  of giving enzymes names ending in 'ase'. The only major exception to this 'ase' is the proteolytic enzymes, whose names