RBSE Class 11 Biology Notes Chapter 1 The Living World

These comprehensive RBSE Class 11 Biology Notes Chapter 1 The Living World will give a brief overview of all the concepts.

RBSE Class 11 Biology Chapter 1 Notes The Living World

→ Biology is the branch of science which deals with the study of various life forms and living processes occur in them.

→ About 1.7-1.8 millions kinds (species) of living organisms are known at present,

→ Detailed system of classification is based on similarities and disimilarities among living organisms.

→ Life is an unique, complex organisation of ions and molecules which perform certain chemical reactions in order to bring about life processes.

→ A living refers to any organism that shows the characteristics of being alive such as presence of protoplasm, cellular organisation, nutrition, metabolism, growth, reproduction and response to environment etc.

→ Protoplasm is called ‘Physical basis of life’.

→ Systematics is the classification of organisms on the basis of evolutionary and other relationships. It enables us to deal with the enormous diversity of life.

 

→ Taxonomy deals with the laws and principles of classifying organisms. Taxon is a group of similar organisms.

→ Grouping levels in classification are termed categories. There are seven categories which in hierarchial order are—kingdom, phylum/division, class, order, family, genus and species.

→ Classifying a group of species and naming them and understand the evolutionary relationships is called revision of the group.

→ Botanical gardens and herbaria educate public about country’s plant wealth and stimulate people to grow more trees.

→ Zoological parks exhibit living organisms. On the otherhand zoological museum display inanimate objects. .

→ Flora, manuals, monographs and catalogues are some other means of recording descriptions of organisms.
 
→ Biodiversity: The variety of living organisms present on a particular area.

→ Life: It is an unique, complex organisation of ions and molecules which perform certain chemical reactions in order to bring about life activities.

→ Protoplasm: Physical basis of life.

→ Morphous: Objects having morphological forms i.e., living organisms.

→ Amorphous: Formless objects. .

→ Growth: Parmanent and irreversible change in the size of a cell, an organ or whole organism.

→ Development: It is the some of changes occur in an organ or an organism during its life times.

→ Reproduction: A property of living organisms to produce more of its own kind.

→ Metabolism: Chemical reactions going in the living cells are collectively termed as metabolism.

→ Anabolism: Biochemical reactions concerned with the synthesis of complex substances from simple ones.

→ Catabolism: Biochemical reactions concerned with the ‘break down’ of organic nutrient molecules into simple substances.

→ Homeostasis: Maintenance of internal body conditions under adverse environmental conditions.

→ Response: Visible change in an organism produces as a result of applied stimulus is called response.

→ Irritability or Sensitivity: Ability of an organism to produce the response against the applied stimulus is called irritability or sensitivity.

→ Adaptations: These are useful inheritable variations or changes that make an organism to adjust well and suited to its way of life.

→ Classifications: Scientific ordering of organisms in a hierarchial series of groups on the basis of their morphological, evolutionary and other relationships.

→ Nomenclature: Scientific naming of organisms.

→ Taxonomy: It is the branch of biology that deals with the framing of laws and principles of classifying the organisms on the basis of their evolutionary relationship.

→ Taxonomic Categories: The various grouping levels or ranks in classification are known as taxonomic categories i.e., kingdom, phylum, class, order, family genus and species.

→ Species: It is a group of actually or potentially inbreeding populations that are reproductively isolated from each other. 

→ Genus: It is a group of species alike in the broad feature but different in detail.

→ Family: A group of related genera, sfs Order: A group of related families.

→ Class: A group of related orders.

→ Phylum: A group of related animal classes.

→ Division: A group of related plant classes.

→ Kingdom: It is the highest category in the biological classification.

→ Herbarium: It is a collection of pressed, dried and preserved plants mounted on paper sheets, properly labelled, systematically arranged and available for reference or study.

→ Botanical Garden: It is a place where plants from various groups are grown for scientific study, conservation, public education, aesthetics and recreation.

→ Zoological Museum: It is a building used for the preservation, storage and exhibition of inanimate objects which illustrate the human or natural history.

→ Zoological Park: An enclosed place where live wild animals are kept for public exhibition.

→ Keys: The term key refers to a set of alternate characters in such a manner that helps in the identification of organisms by selecting and eliminating the characters according to their presence or absence in the organism under study.