These are derivatives of fluorene-9-carboxylic acid and are absorbed through the seeds, roots and leaves.
The role of morphactins is usually of inhibitory in nature. They are responsible for complete abolition of polarity in plants, inhibition of mitosis in apical meristem, abolition of geotropic and phototropic responses etc.
The growth process in plants is controlled by combined action of various hormones. The amount or concentrations of different hormones along with environmental factors determine the growth in plants.
Since plant hormones were discovered later to animal hormones early researchers suggested that both the hormones have similar physiological effects. But there are some basic differences between the two.
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Certain responses of phytohormones can be obtained by applying phytohormones to various parts of the plants, but this does not necessarily mean that such responses are naturally controlled by hormone.
Further, animal hormones are produced by specific endocrine glands whereas phytohormones are produced by actively metabolizing tissues that carry out other functions too. Each animal hormone has a specific target tissue or organ whereas plant hormones act on a variety of tissues.
As a result of these basic differences, the botanists, therefore, refer the phytohormones as plant growth regulators and suggest that plant growth regulators are integrating agents, that are necessary for, but do not control the response. For example, cytokines regulate the breaking of dormancy in bud, but do not control the subsequent growth of bud. So they are necessary for bud growth, but do not control it.
There is also a distinction between hormones and, nutrients. The hormones are required in extremely minute quantities in comparison to the nutrients.
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The hormones also differ from enzymes. The enzymes are essential to initiate and continue the reactions but hormones only influence the reactions. Further, hormones are usually consumed in the process of growth while enzymes are not.
Both the strands have sugar phosphate backbone and are anti parallel to one another. The anti parallel nature is given by orientation of the deoxyribose sugar which is opposite in both the strands.
Therefore the 5th carbon atom of the sugar molecule, which is exposed at one end of a strand (5′ end), faces the 3rd carbon atom of the sugar in the opposite strand (3′ end). The strands are also complementary to each other.
This nature is based on the purine-pyrimidine links i.e. if one strand is having a purine base (adenine or guanine) other strand must have a pyrimidine counterpart (cytosine or thymine) e.g. A = T and /G = C. In DNA the nucleosides are joined by means of phosphodiester bonds. RNA
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RNA is a polynucleotide made of ribonucleotide units having ribose sugar, phosphoric acid and one of the nitrogen bases (Adenine, Guanine, Cytosine, and Uracil). It is single stranded. Cellular RNAs are non-genetic and are of three types.