To classify a class of forty students, let us start the classification on the basis of sexes of the students. This classification will result in the formation of two major groups- boys and girls. Each of these two groups can be further classified on the basis of the names of the students falling in these groups. Since it is possible that more than one student can have a particular name, these names can be further divided based on the surnames. Since there is still some chance that more than one student can have the same surname, the final level of classification will be based on the roll numbers of each student.
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a. | Herbarium | i. | It is a place having a collection of preserved plants and animals. |
b. | Key | ii. | A list that enumerates methodically all the species found in an area with brief description aiding identification. |
c. | Museum | iii. | Is a place where dried and pressed plant specimens mounted on sheets are kept. |
d. | Catalogue | iv. | A booklet containing a list of characters and their alternates which are helpful in identification of various taxa. |
Figures 9.20(a) and (b) refer to the steady flow of a (non-viscous) liquid. Which of the two figures is incorrect ? Why ?