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J. G. Sikdar
This may be interpreted as the sexual union of this treed. It is suggestive from this evidence that sexual reproduction also may take place in plant life. But according to Janna biology, there is no clear reference to sexual reproduction in plants, which involves the co-operation of two parents, each of which supplies one gamete and two gametes unite to form zygote. Very vague ideas are contained in other Indian works42 as to the soxual reproduction of plants
The Life Cycle of Plant The life cycle of any species of plants or animals is the biologic process of development which takes place between any given point 10 any organism's life-span and the same point in the life-span of its offspring For bacteria (earth quadrates 4a and plant bacteria.), blue-greeas (alage=Saryala)45 which reproduce by splitting (a kind of asexual reporduction), the life cycle is extremely simple. According to modern Biology, "The filamentous green algae such as, Ulothrix, have a cycle during most of which, the colony consista of haploid cells which multiply asexually by mitosis"40,
In the higher plants there are clearly found their life cycle-stages of infancy, youth and age17 like those of human body, etc. Parasitic plants have complex life cycles involving host organisms
According to Jaina Biology, the plants show an act of generationgeneration wbich reproduces asexually by spores 60 It is known as the sporopbyte. Besides, they are reproduced from the root, the knot and the stem 61 The life cycle of such plants consists of the production of haploid spores by the sporopbyte The relative size and duration of the different sporophyte generations vary considerably. The aporophyte is the familiar Visible tree, shrub or herb
Germination of the Seed and Embryonic Development. Jaida Biology throws some welcome light upon the germination of the seed and embryonic development. When the seeds are ripe, they are shed from the parent plant, but a few of them do germinate shortly after being shed, most of them remajn dormant during the cold or dry season and germinate only with the advent of the next favourable growing season 52 A prolonged period of dormancy usually occurs only 10 seeds with thick or waxy sed coats which ronder them impenetrable to water and oxygen.
The life of some higher plants exists within the cover of seeds 10 state of dormancy to be awakened at proper timo and season under the favourable conditions The life persists within the protective seed coat for certain perioda, regiating against all the forces of the natural phenomena, In due time and season this dorment life spriags up, burating asunder the
