Growth in biological terms is characteristic feature of all living organisms. It relates to increase in size by accumulation of protoplasm in the cell thus results in increase in size of the cell. Whereas increase in number of cell by cell division results is the size of individual organism.

Snow is an inanimate (non-living) object, while rolling over snow, it gathers more snow on its surface thus, it increases in size by physical phenomenon but not by biological phenomenon. So, this growth cannot be compared to that seen in living organisms.

In a given habitat, there are existing 20 plant species and 20 animal species. They will of course exhibit the biodiversity of that given habitat because diversity refers to variation in a broad term and can be applied to any area. Whereas biodiversity is a degree of variation of life forms within a specified area.

ICBN has specified certain rules and principles is order to facilitate the study of plants by botanists. It helps in correct positioning of any newly discovered organism through proper identification and nomenclature.

Given below is the taxonomic hierarchy, which is used while classifying any plant Kingdom-Plantae

Division-phyta

Class-ae

Order-ales

Family-eae/ceae

Genus-First name of organism usually carrying Latin word and written in italics.

Species-Second word of scientific name, also written in italics.

These variants are called biotypes. It is a group of genetically similar plants showing similarity when grown in same environmental and geographical regions. The same environment provide them the similar abiotic factors like soil, pH , temperature, etc. When they are grown in two different geographical regions, they are exposed to different abiotic characters thus, it affects their growth and development bringing changes in their external morphological features but, they have the same genetic constitution.

For preservation of plant material on a herbarium sheet the following tools and steps are required to be followed.

Tools Digger and pruning knife, sickle with long handle, vasculum, polythene bags, magazines or newspapers, blotting papers, plant press, field notebook, herbarium sheets, glue, labels, small transparent polythene bags.

One can prepare herbarium sheets by cutting papers of size $29 \times 41.5 \mathrm{~cm}\left(11 \frac{1}{2} \times 16 \frac{1}{2}\right)^{\prime \prime}$.

The preparation of a herbarium specimen required following steps

(i) Collection of plant or plant parts.

(ii) Pressing It involves the spreading and pressing of collected specimen over a newspaper so as to preserve its all parts.

(iii) Drying It involves the drying of the specimen between the folds of newspaper.

(iv) Poisoning Antifungal (dipping in $2 \% \mathrm{HgCl}_2$ ) and pesticidal (DDT) treatment of the dried specimen.

(v) Mounting It involves mounting of the specimen over a herbarium sheet.

(vi) Labelling and identification of the dried specimen are the last steps, while preparing a herbarium sheet.

Tools/equipments required for the collection of herbarium specimens are as follows

(i) A tin or aluminium container of $50 \times 30 \times 15 \mathrm{~cm}$ size.

(ii) Collection bags/plastic/polythene bags.

(iii) Digger for digging roots.

(iv) Magnifying lens of at least 10X magnification.

(v) Field note book.

A preserved plant material on the herbarium sheet may provide information about the family, genus, species, date of collection, area of collection, etc., for taxonomic studies.