Q. 20. Give the diagramatic life cycle of Ephedra. (1997)
Related Questions -
Q. With the help of a labelled diagrams only describe the life cycle of Ephedra. (2004)
Ans.
Q.21. Write economic importance of Ephedra. (2005, 07, 09, 13)
Related Questions -
Q. Give source of Ephedrine. (2010)
Ans. Economic Importance of Ephedra: -
Economic importance of Ephedra is less than other gymnosperms.
The valuable drug ‘Ephedrine’ is obtained from Asiatic species : E. gerardiana. E. nebrodensis, E. intermedia and E.sinica. It is used in the treatment of asthma and hay fever. Tuberculosis, tonsils related disease.
E. gerardiana is used for the production of tincture. It is used as a stimulater for increasing blood circulation and heart beat. The extract which is isolated from the roots and stems of Ephedra used for the treatment of Arthritis and Syphilis.
Extract of seed is used for the treatment of blood and respiration related disease.
Some species of Ephedra are used as a ornamental plants in garden. Rhizomes of E. gerardiana are utilized as fuel by the peaple of Tibet.
Q.22. What are fossils? Explain their fosilization and types of fossils. (2012, 13)
Ans. The fossils means the remains of organism that lived long ago. Fossil is derived from a Latin word fodere meaning “to dig”. In fact fossils are impression or cast of the organelles organism, living sometime back but now extinct, on the rock occurring in the earth and requiring to be dug out.
Normally the plant dies and it immediately starts degeneration. This degeneration remains continuous till the entire body is broken into single chemical compound-by which no evidences of its former remain in existence. But sometimes under certain circumstances the degeneration of plant body stops and part of the body remain in visible form. These remains known as fossils. These fossils are lifeless and in capable of stimulus.
Plant fossils are normally prescribed in rocks composed sediments deposited in waters. These stratified rocks are superimposed upon one another in series. These rocks are built of sediments that accumulate in bottom of seas, lakes, swamps, flooded valleys subsiding beaches, etc. The rock formation is correlated with the geological approach in the subject paleobotany. In fact fossils are the makers of geologic time. The study of botany as well as geology is essential for the study of fossil plants. The classification of fossil plant is very difficult as there are much chances for errors.
Fosilization: -
First of all the part of stem borne plant come into quite water and become saturated. Now it begins to sink. The entire plant or some part of it lie in parallel to horizontal position. In presence of mud or sand plant will settle with sand. Abundant sedimentation will cause rapid accumulation and the plants will be separated from one another. Thus rocks are formed in between which plants parts (mainly stem leaves) remain present. The weight of the accumulating sediments will flatten it. As the sediments increase in thickness, compact in result and the less resistant and more compressible plant parts flattened to new portion of its original thickness. The plant part if is cylindrical and made up of hard tissues the weight over of sediments will produce a lens shaped object. Thus the rocks having compression and impression of plant. Thus the rocks having compression when split open or one surface usually bears the impressed outer part.
Types of Fossil plants: -
Some of the important type of plants fossils are as follows:
(1) Peterification of Mineralised plants: -
In this type of plant fossil the original cell of the plant tissue is retained by means of some minerals like CaCO3 silica, etc., that has infiltrated the tissues. In this types of fossil sometimes the material of original plant may be preserved, e.g., coal balls, silicified wood, etc.
(2) Cast or Encrustations: -
In this type of plant fossil, the form of plant preserved as a cast. The cast result from the filling of a cavity formed by decay of tissues of plant part. Here the internal structures are destroyed and carbonaceous substance of the plant has totally gone, e.g., stem leaf scars, larges seeds.
(3) Compression: -
In this type of plant fossil, the external form of plant modifies and leaves impression on the sediment which overlie it.
(4) Compaction of Mummified plants: -
In this type of plant fossil, the plant or their parts get compressed by vertical pressure against one another. Mostly plant rudiments found in peat and coal as compactions.
Coal or coal balls are the important sources of plant fossils. Coal are irregular or subspherical mass of calcium or magnesium carbonates (or some other mineral matter).
(5) Impressions: -
In this types of plants fossil-the roots, stems, leaves, fruits and seeds are preserved as impressions in such a fashion that they seem to the actual direct specimens laid on the stone.