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Class 11th Biology Chapter~1 The living world

Unit :-1
Diversity in the living world

=> Earnst Mayr, was called as the Darwin of the 20th century

:- He pioneered the currently accepted defination of a biological species.

Biological species - Two species which interbreed themselves

• A taxonomist is a biologist that groups organisms into categories.


The living world

=> Features of living organisms
• Metabolic activity
• Ability to self-replicate
• sepf-organise
• Interact or adapt themselves in their surroundings

=> All living organisms grow.

π. Increase in mass and increase in number of individuals are twin characteristics of higher animal & plants, growth & reproduction are mutually exclusive events

π. It means that they cannot occur at the same time.

* mountain, bouders and sand mounds do grow but they are not living things.
* Internal growth is the defining property of living organisms.

=> Reproduction is another characteristics of living organisms.
• Fungi : asexual spores
• Yeast and Hydra : Budding
• planaria ( flat worms ) : True regeneration
• The fungi the filamentous algae, the protonema of mosses, all easily multiply by fragmentation.
• Unicellular organisms like bacteria, unicellular algae or Amoeba, Reproduction is synonymous with growth, i.e increase in number of cells

* Many organisms which do not reproduce ( mules, sterile worker bees, infertile human couple, etc.

=> Another characteristics of life is metabolism.
• The total of all the chemical reaction occuring in our body is metabolism.
• An isolated metabolic reaction (s) outside the body of an organism, performed in a test tube is neither living nor non-living.
• Isolated metabolic reaction in-vitro are not living things but surely living reactions.

:- In-vitro is used to describe work that's performed outside of a living organisms.

* Metabolism is a defining features of all living organisms ( organisation ) of the body is the defining features of life forms.

=> Consciousness therefore, become the defining property of living organisms.

• The most obvious & technically complicated features of all living organisms is this ability to scene their surroundings or environment and respond to these environment stimuli.
• Plants respond to external factors like light, water, temperature, other organisms pollutants, etc. All organisms from the prokaryotic to the complex eukaryotes.
• Photoperiod affect reproduction in seasonal breeders, both plants & animals.
• Human is the only organisms who is aware himself, i.e , has self-consciousness

*Coma patients are living because hospital virtually supported by machine which replace heart & lungs.

* Living organisms are self- replicating, evolving & self-regulating interactive systems capable of responding to external stimuli.

* Taxonomy is the process of naming & classifying things such as animals and plants into groups within a larger system, according to their similarities & difference.

=> There are 1.7 to 1.8 known & describe range of species.

:- This refers to biodiversity or the number & types of organisms present on the earth.

Naming of species as follows:-

1) Identification

:- Recognition of the identity or essential character of an organism.

2) Nomenclature

:- System for giving names to things within a particular profession or field.

# Binomial nomenclature
• The system of nomenclature in which two terms are used to donate a species of living organisms the first one indicating the genus & the second the specific epithet.

π Given by Carolus Linnaeus

3) classification

:- The process by which scientists groups living organisms.
:- Determined by examining the physical characteristics of an organism but classification uses a variety of techniques including genetic analysis.

* International code or Botanical Nomenclature.[ICBN]
* International code for Zoological Nomenclature.[ICZN]

Universal rules of Nomenclature are:-
1. Biological names are generally in Latin & written in Italics. They are Latinised or derived from irrespective of their origin.
2. The first word in a biological name represent the genus while the second component denotes the specific epithet.
3. Both the words in a biological name, when handwritten, are sperately underlined, or printed in Italics to indicate their Latin origin.
4. The first word donating the genus start with a capital letters start while the specific epithet start with a small letter.

E.g:- Mangifera indica (Mango)

* Taxa can indicate categories at very different levels

=> External & Internal structure, along with the structure of cell, development process and ecdogical information of organisms are essential & form the basis of modern taxonomic studies.
=> Characterisation, identification & Nomenclature & classification are the process that are basic to taxonomy

# Relationship between organisms & their diversities.
This branch of study was referred to as systematic.
:- systema means systematic arrangement of organisms.
:- It takes account evolutionary relationship b/w organisms.

* Systema naturae book by carl Linnaeus.

=> The category is a part of overall taxonomic arrangements, it is called the taxonomic categay.

π all categories together constitute the taxonomy hierarchy.

π category, referred to as unit of classification, in fact, represent a rank is commonly termed as taxon.

π Group represent category & category further denotes rank.

How animals are classified

Trick to learn: Dear king philip came over for good soul.

How plants are classified:-

1. Species
• A group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding.
• Mangifera indica (Mango)
• panthera leo (lion)
:- Here indica, tuberosum, and leo represent specific epithet while Mangifera, solanum, panthera represent genera & another higher level of taxon or category.

* Each genus may have one or more than one specific epithets representing different organisms.

:- for e.g : panthera hqs another specific epithet called tigris & solanum includes species like higrum & melongena.

:- Humans being belong to the specific sapiens which is grouped in the genus homo.

2. Genus
• Genus comprises a group of related species which has more characters in common in comparison to species of other genera.
• potato and brinjal different species but same Genus solar.
• Lion (p.leo), leopard ( p.pardus) & tiger (p.tigris)

π p stand for panthera.
π This genus differ from another genus Felis which includes cats.

3. Family
• families are characterized on the basis of both vegetative and reproductive feature of plant species.
• three different genera solanum, petunia & Datura are placed in the family solanacea.
• Lion, Tiger and leopard placed in the family panthera.
• Felis (cat) in Felidae family.
• on the basis of similarities and disimilarities cat and dog seperated into two different families falidue & canidae

4. Order
• Convolvulaceae, solanacea are included in the order polymoniabs mainly based on the floral characters
• the animal order, carnivora, families include families like Felidae & canidae.

5. Class
• Order primata comprising monkey, Godzilla and gibbon is placed in class mommulia along with order carnivora.

6. Phylum
• Classes comprising animal like fishes, amphibians, birds along with mammals constitute the next higher category called
• phylum

π Based on notochord & dorsol hollow neural system are included in phylum chordata

• Classes with a few similar characters are assigned to a higher category called division in plant.

* Notochord is a cartilaginous skeletal rod supporting the body in all embryonic & adut chordate animals.

7. Kingdom

• These are board categories
• Kingdom animalia.
• Kingdom plantae.
• as we go higher from species to Kingdom, the number of common characteristics goes on decrising
• lower the taxa, more are the characteristics that the members within the taxon share.
• Higher the category, greater is the difficulty of determining the relationship to other taxa at the same level.

Organisms with their taxonomic categories

1. Common Name
2. Biological Name
3. Genus
4. Family
5. Order
6. Class
7. Phylum/Division

1. Man
2. Homo sapiens
3. Homo
4. Hominidae
5. Primata
6. Mammalia
7. Chordata

1. Housefly
2. Musca domestica
3. Musca
4. Muscidae
5. Diptera
6. Insecia
7. Arthropoda

1. Mango
2. Magnifera indica
3. Magnifera
4. Anacardiaceae
5. Sapindales
6. Dicotyledonae
7. Angiospermae

2.Triticum aestivum
3. Triticum
4. Poaceae
5. Poales
6. Monocotyledonae
7. Angiospermae

1. Tulsi

Taxonomical Aids
• Taxonomic studies of various species of plants, animals & other organisms are useful in agriculture, forestry, Industry & in general in knowing our bio-resource and their diversity
• Taxonomic aids are techniques, procedure and stored information that are helpful in identification and classification of organisms. Herbarium, Biological garden, Museum, zoological parks & key are the example of Taxonomical Aids.
• The collection of actual specimens of plant and animal species is essential is the prime source of Taxonomic studies.

1. Herbarium

• Herbarium is a stor house of collected plants specimens that are dried, pressed and preserved on sheets.
• specimens are mounted on sheets of standard size herbarium paper 29 x 42cm
• universally accepted system of classification
• The herbarium sheets also carry on level providing information about date and place of collections, English, local and botanical names, family, collector name.
• Herbaria also serve as quick referral system

2. Botanical gardens
• Specialised gardens have collections of living plants for reference.
• kew, Royal Gardens in London is the world's largest botanical garden
• Indian Botanical garden, Howrah (India)
• National Botanical Research Institute, Lucknow (India).

3. Museum
• Museum is an institutions where artistic & educational material are exhibited to the public.
• The material available for observations & study are called a collection.
• Insect are preserved in insect boxes after collecting, killing and pinning.
• Larger animal like birds and mammals are usually stuffed and preserved.
• Museum offten have collections of skeletons of animals too.

4. Zoological park

• A park or an institution in which living animals are kept and usually exhibited to the public.
• The main reason of setting Zoological park are to maintain ecological balance in the environment and conserve wildlife.

5. Key

• Taxonomic key is one of the most useful tool available to scientist trying to identify an unknown organism.
• The key is based on contrasting characters generally in a pair called couplet.
• couplet represent the choice made b/w two opposite options.

π results in ecceptance of only one & rejection of the other.

• Each statement in the key is called a lead.
• key are generally analytical in nature.

• flora contains the actual account of habitat and distribution of plant of a given area.
• These provide the index to the plant. species found in a particular area.
• Information booklet.

* Manuals are useful in providing information for identification of name of species found in an area.

* Monographs contain information on any one taxon.

* Describtion about any book, any writer or publisher is given in catalogues.

* Taxonomists also prepare & disseminate information through manuals & monographs for future taxonomic studies.

Class 10 English Footprints Without Feet

  1. Chapter 1- A Triumph of Surgery
  2. Chapter 2- The Thief's Story
  3. Chapter 3- The Midnight Visitor
  4. Chapter 4- A Question of Trust
  5. Chapter 5- Footprints without Feet
  6. Chapter 6- The Making of a Scientist
  7. Chapter 7- The Necklace
  8. Chapter 8- The Hack Driver
  9. Chapter 9- Bholi
  10. Chapter 10- The Book That Saved the Earth

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