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
A saline drip is to be prepared for a lab experiment that is looking at hydration in lab rats. Calculate the amount of NaCl need to make 4 liters of a 0.9% solution.

Energy Allowance: Energy Allowance: The  patient's requirement for  energy  varies with the physical activity and physiological condition. For instance, consider a person con

How does water move inside sponges? What is the function of the pores in these animals? Sponges are filtering beings. They make water enter their bodies by their lateral pores

Explain the Formation of enzyme? Formation of enzyme: Vitamin D is essential for the formation of two enzymes -  alkaline phosphtase in the intestinal lining (involved in cal

Explain Regulatory enzymes Regulatory enzymes:   Citrate  synthase,  isocitrate  dehydrogenase  and a-ketoglutarate dehydrogenase complex are the key  enzymes which  regulate

Protraction from HIV  Under the following conditions HIV is not transmitted 1) The secretions and body fluids like Saliva, Tears, Sweat, Faeces, and Urine have negligible HIV c

Cytology: The study of form or culture including the behavior of nucleus and other organelles is called cytology. Cytology means "the study of cells". Cytology is the branch of lif

What morphological structure is responsible for bacterial motility?

Name and describe any three adaptations of mangroves to the conditions prevailing in the Sunderbans.

Determine the Types of Exercises Exercises are generally grouped  into three types: - Flexibility exercises such as stretching improves the range of motion of muscles and jo