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Thus, Series under a Class, Classes under a Division and several Divisions form the Plant Kingdom.
In animal classification
6. Similar classes are grouped into PHYLA (sing. PHYLUM)
BINOMIAL NOMENCLATURE
In classifying a plant or an animal, it is necessary to label it by some name. Normally a plant or an animal is known by its local or popular name which differs from place to place. Therefore, Carolus Linnaeus, a Swedish naturalist, introduced a system of binomial nomenclature. According to this system, every plant and animal is given a double name first its generic (GENUS) and second its specific (SPECIES). Its application by Linneeus in 1753 to plants and in 1758 to animals is now followed universally.
FORM, STRUCTURE, AND CLASSIFICATION OF PLANTS
The main organs of a plant are: root, stem, branches, leaves, flowers, fruits and seeds. Of these root, stem and leaves carry out functions like nutrition and growth and are called vegetative organs while flowers, fruits and seeds are reproductive organs.
1. ROOT
The root is the descending organ which grows towards the soil and fixes the plant to the soil from which it absorbs nutrition for the plant. The primary root grows downwards to form the main root called the tap root. From the main root are produced lateral roots—secondary roots, which branch further into tertiary roots. All these form the tap root system. Roots that grow from any part of the plant other than the radicle are called adventitious roots.
The normal functions of a root are :
i. to fix the plant firmly to the soil
ii. to absorb raw food material (water & minerals) from the soil through the root hairs.
-:14: Jain Education International
JAIN BIOLOGY
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