Monera

i)Monera includes all the organisms which lack a well organised nucleus and membrane bound cell organelles.

ii) Monera are made up of prokaryotic cell.

iii) Monera possess circular DNA.

iv) Monera are small and microscopic.

v) Monera are commonly exist as single cell or group of cells.

vi) Monera are found everywhere on the earth.

vii) Monera are found in hot springs on the underside of icebergs on the deep ocean floor, in the hottest and driest deserts as parasites and in other life forms.

viii) Most of the moneras have rigid cell wall.

ix) Monera are autotropic as well as heterotropic in nutrition.

x) Monera are known as decomposers and mineralisers in the biosphere.

Monera includes three major groups they are Bacteria, Cyanobacteria and Archaebacteria.

Five Kingdom System Of Classification

R.H whittaker in 1969 proposed five kingdom classification. In this system the arrangement of five kingdoms is based on following three criterias:

i) The complexity of cell structure i.e Prokaryote and Eukaryote.

ii) The complexity of the organisms body- unicellular and multicellular.

iii) The mode of obtaining nutrition - Autotrops and Heterotrops.

The five kingdoms are Monera, Protista, Plantae, Fungi, Animalia where monerans are microscopic prokaryotes with incipient nucleus which lacks membrane bound cell organelles, protista are aquatic, unicellular eukaryotes which have an organised nucleus, membrane bound cell organelles, Plantae includes multicellular, photosynthetic, eukaryotes with cellulose cell wall, Fungi are multicellular, eukaryotic and heterotropic decomposer, Animalia are multicellulareukaryotes haaving locomotory organs, heterotropic mode of nutrition these includes sponges to mammals.

Shortcommings Of Two kingdoms Classification

The history of taxonomy of organisms shows that the taxonomist always tried to classify the living organisms into two organisms into two distinct kingdoms Plantae and Animalia. Hence, these system of classification are known as two kingdom system.

1. Plantae : It includes all the organisms which show :

i) Autotrophic nutrition.

ii) Sedentary habitat (fixed in a place).

iii) Presence of cellulose cell wall.

iv) spread out appearance.

It includes all the green plants, mosses, fungi, lichens, bacteria.

2. Animalia : It includes all the organisms which show

i) Heterotropic nutrition

ii) Locomotion

iii) Absence of cellulose cell wall.

It included all unicellular and multicellular animals. The grouping of such diverse organism into two kingdoms has appeared unsatisfactory to many biologists.

a) It puts together eukaryotes (organisms with true nucleus in their cells) with prokaryotes (organisms without true nucleus)

b) It placed non-photosynthetic fungi together with photosynthetic fungi together with photosynthetic green plants.

c) Many singled celled animals like euglena have features of both plants and animals.

d) Some unicellular organisms like slime moulds lack a cell wall in the vegetative stage but develop one during the reproduction stage.

e) Bacteria could not be classified as plants or animals.

Binomial Nomenclature

The system of naming of properly identified plants and animals according to the nomenclatural system is known as nomenclature. In binomial nomenclature the scientific name of an organism consists of two names in Latin. The first is the generic name and second is the specific name. The name of scientist who first described the plant is also written after the species in an abbreviated or full form e.g. the scientific name name of potato is Solanum tuberosum Linn where Solanum is genus and tuberosum is species and Linn is the abbreviated form of Linnaenus. Binomial system was at first used by Swedish naturalist Casper Bauhin (1560-1624). That was elaborated by Carolus Linnaeus in his species Plantarum 1753. However, the rules of nomenclature system had their beginning in Linnaeus "Critica Botanica" in 1737. Critica Botanica was written primarily to explain the taxonomic and was adopted by the International Botanical congress held in Vienna, 1905. According to Binomial nomenclature system the generic name of plant begin with the capital letter and the specific name is always proceeded with by the generic name. The scientific names are always italicized or underlined.

Taxonomic hierarchy : The arrangement of taxonomic categories in their proper order on the basis of their taxonomic ranks is called taxonomic hierarchy. In taxonomic hierarchy the kingdom represents the category of highest rank while the species represents the lowermost rank. The categories of classifications are kingdom, sub kingdom, Division/Phylum, Class, Sub class, Order, Family, Genus and Species.

History Of Taxonomy

Contribution of some Biologists

Aristotle (384-322) : The Greek Philosopher and biologist of 4th century B.C. have classified plants and animals. Plants as herbs, shrubs and trees. Animals are grouped according to their habitat and have also attempt to classify plants based on their medicinal properties.

Charak (1st century A.D) : Charak is known as father of Ayurveda. He listed the names of more than 200 kinds of animals and 340 kinds of plants in his book charaka samhita on Indian medicine.

Theophrastus (370-285 B.C) : A student of his great Greek Philosopher Aristotle known as father of Botany. His excellent contributions form the foundation of botanical knowledge. In his book " History Of Plants" he described 480 species of plants mostly cultivated. He classified plants on the basis of forms or texture into four groups. Herbs,shrubs and trees. He distinguished between annual,biennial and perennial plants.

John Ray (1627-1705) : An English taxonomist. He presented a system based on collecting of 18000 species in his book "Historia Plantarum". We find some of the first indications of a natural system of classification. He introduced the term species for one kind of living organisms forming natural groups.

Taxonomy

The word taxonomy is derived from two Greek words "taxis" meaning arrangement or classification and "nomos" meaning law or rules. Thus literally taxonomy can be defined as the law
of arrangement or classification of organisms. In broadest sense, Taxomomy may be defined as the branch of biology which deals with identification, nomenclature and classification of organisms.
Identifications is the determination of an unknown object either by comparision with a known object.
Nomenclature or naming is the determination of the correct name of a known object according to the nomenclatural system.
Classification is the placing of an organism in definite groups (division,class,order,family,genus and species) according to a particular plan or sequence and in conformity with a nomenclatural system. The word biology is so rich that scientists have yet to explore all of it. There are millions of organism. A general estimate of the number of species of living organisms existing today is 5 to 30 million. Many of them have been named and a few have been studied in detail while rest are unknown. Everyday new organisms are being discovered and the list of known plants are ever increasing. The study and knowledge of all these organisms will be highly confusing, meaningless and useless if they are not properly identified and arranged systematically. Therefore the organisms are identified, named and placed into small or large groups on the basis of their similarities and differences.

Differences Between Apes And Man

i) Apes have small brain box ranging from 395cc, orangutan 400cc, Chimpanzee 400cc, Gorilla 520cc but man has much larger brain box 1200-1450cc.

ii) Occipital condyles posterior in apes whereas occipital condyles anterior in man.

iii) Apes have a semi erect posture but man has fully erect posture.

iv) The back bone forms a simple curving arch in Apes whereas the back bone forms s-shaped curve and supports the body weight well in man.

v) In Apes head is buried in the heavy shoulders but head is well placed on slender neck in man.

vi) Massive jaws without prominent chin is present in Apes whereas small Jaws with prominent chin is present in man.

vii) Incisors and canine teeth are larger in Apes but Incisors and canine teeth are smaller in man.

viii) Arms are longer than legs in Apes but Arms are shorter than legs in man.

ix) In apes neck muscles allow less movement of the head on the neck but in man neck muscles allow more movement of head on neck.

x) The thumb doesnt reach the base of the fore fingers in apes but the thumb extends up to the middle joint of the finger in man.

xi) Apes have much less ability and cannot manufacture tools whereas man has the ability to make and employ tools, speak and write well.