The Living World Chapter Notes | Biology for ACT PDF Download

The Living World

For an organism to be living, there are some features that are imperative. These features are:

1. Growth
2. Reproduction
3. Tactile sensation, Ability to sense the environment
4. Metabolism
5. Self-organize
6. Mortality 

Since all processes occur in the protoplasm, Huxley rightly called it the physical basis of life. It exhibits all the properties of life, hence it is known as the living matter.

Important Terms

1. Nomenclature

• The process of rendering scientific names to organisms. ICBN and ICZN were advanced to appoint scientific names for plants and animals separately. 
• The scientific name has two segments – the generic name and the specific epithet. This arrangement of providing a name with two components is called Binomial Nomenclature given by Carolus Linnaeus.
  Example: Homo sapiens. Here ‘Homo’ is the generic name and sapiens is the specific epithet.

Rules for Nomenclature

• Each name has two words – the genus and the specific epithet
• When expressed, should be independently underlined when written manually and should be italics when printed
• Names should be Latinized or in Latin
• Generic name begins with upper case and the specific name begins with lower case

Question-related to Nomenclature has been asked in NEET - I 2016

Question: Nomenclature is governed by certain universal rules. Which one of the following is contrary to the rules of nomenclature?
(a) The names are written in Latin and are italicized.
(b) When written by hand, the names are to be underlined.
(c) Biological names can be written in any language.
(d) The first word in a biological name represents the genus name, and the second
is a specific epithet.

Ans: (c)

Binomial nomenclature means naming an organism with two words. The first word represents the genus and the second word represents species. The first letter of the genus is always written in the capital letter and the first letter of species in small letter. The names are always written in the Latin language as they are mostly derived from Latin and Greek. These are italicized in the font. If written with the hand they are underlined. These can't be written in any other languages as these are rules followed worldwide in nomenclature

So, the correct answer is 'Biological names can be written in any language'

2. Classification

• It is the process of assigning creatures in specific classes or groups considering some defined characters. 
• These groups are known as taxa.

3. Taxonomy

• It is the process of identification, nomenclature and organization of life forms considering the inner and outer cell structure, biological data and advancement process

4. Systematics

• Investigating life forms in association with identification, nomenclature, arrangement and evolutionary correspondence. Linnaeus used Systema Naturae as the title of his publication

5. Taxonomic Categories

• It depicts the rank or level in the hierarchical arrangement in ascending order. The seven mandatory categories are: Kingdom > Division > Class > Order > Family > Genus > Species

• Kingdom – includes different phyla of animals and different plant divisions.
• Division/Phylum – incorporates related classes as a division in plants and phylum in animals
• Class – Many orders related to each other are incorporated into a class.
• Order – includes a few related families
• Family – it is an assembly of related genera
• Genus – a gathering of related animal categories having similar characters
• Species – the essential unit in classification, species refers to the individuals from any animal group that are firmly related, obtained from a typical ancestor which can interbreed to produce offsprings that are fertile themselves.

Points to Remember

• The Father of Indian Taxonomy is H Santapau.
• The Father of Indian Botany and Indian Herbaria is William Roxburgh.
• Term ‘taxonomy’ was coined by A.P. de Candolle (French botanist). The book "Théorie élémentaire de la Botanique" is also written by him.
• The Father of Taxonomy is Carolus Linnaeus.
• Dynamic concept stating species is dynamic and mutable was given by Lamarck.
• The biological concept of species was given by Dobzhansky and Mayr.
• The Darwin of the 20th century is Ernst Mayr.

Some Famous Books and their Authors

Old NCERT Syllabus

Taxonomical Aids

• Taxonomic guide or taxonomic aids refers to the techniques, stored information and procedures useful in the identification and classification of entities. They are:

1. Herbarium
   A herbarium is the storeroom of assembled plant samples. These samples are dried, squeezed and protected on sheets after which they are systematically ordered in accordance with the classification system universally accepted. The Herbarium sheet consists of marks concerning the scientific name, date, the spot of gathering, name of the collector, family and much more concerning the sample.
2. Museums
   It is a repository, having an assembly of different plant and animal samples preserved for study and further information sources. Here the entities are preserved either as dry samples or in additive arrangements. It usually has an accumulation of skeletons of animals too.
3. Zoological park
   Here, wild animals are ensured with secured conditions of nature. Renders a good chance to focus on the behavioural aspects and sustenance inclinations for these animals.
4. Botanical Garden
   It consists of an accumulation of living plant species developed to identify and also as an information source. Every plant has a label exhibiting its scientific name and family name.
5. Key 
   Used for identifying both plants and animals in light of similarities and dissimilarities.