promotion regulation

This gene is located adjacent to the operator gene. It has two functions. 1.The promoter gene marks the site at which the RNA polymerase enzyme binds. When the operator gene is turned on, the enzyme moves over the operator gene to reach the structural genes and the transcription of mRNA ..

Growth Regulators - The growth of plants is regulated by certain chemical substances, which are synthesized by the plant in very small quantities. These substances are formed in one tissue or organ of the plant and are then transported to other sites where they produce specific ..

Summary - Protein synthesis is a controlled process in which a given protein is synthesised in the cell only when it is necessary. When a particular protein is to be synthesised the specific gene has to express and initiate transcription. The mechanism that stimulates the expression of certain gene..

: Various structural genes involved in a particular metabolic pathway are often not located adjacent to one another. They usually occur far apart on the same or even different chromosomes. The structural gene has coding and non-coding segments called exons and introns respectively. Each structural ..

Gibberellins have been shown to be effective in breaking the dormancy in potato tubers and in tree buds in winter. Cytokinins have been found to be effective in breaking the dormancy of seeds. They also promote the germination of the seeds. The cytokinins substitute the red light requirem..

There are several known growth regulators. Some of them like auxins, cytokinins are growth promoting while others like abscissic acid, ethylene are growth inhibitors. Most of the growth regulators are synthesized by plants while a few are synthetic in natur..

. These chemicals are called the growth regulators as they either promote or inhibit the growth of the plants. Flowering and seed germination are regulated by the duration of light. This is known as photoperiodism. Plants respond to photoperiodism by a specialised pigm..

>Apart from these, nastic movement may also be observed in some plants. This is the movement of plant parts caused by an external stimulus but unaffected in direction by it. Example: The leaves of the 'touch -me - not' plant droop on touching. The growth of the plants, their development and their r..

: Orchids and other plants which support the animal life It regulates the evaporation of water from the body of land organisms during transpiration and perspiration. It promotes the germination of spores in fung..

Protein synthesis is a controlled process in which a given protein is synthesised in the cell only when it is necessary. When a particular protein is to be synthesised the specific gene has to express and initiate transcription. The mechanism that stimulates the expression of certain genes ..