Systems of classification - class-XI

Each category is referred to as a unit of classification or rank and is commonly called taxon. A taxon is a general term for grouping in a systematic classification. A taxon refers to a group of similar and genetically related individuals having certain characters different from other groups.
Correct answer is option B.

In biological classification, the taxonomic rank genus is the relative level of a group of genus-group names and species-group names. Therefore, the genus is interpolated between family and species.

The Kangaroo and Monkey...Belong To the Kingdom animalia..of Phylum Chordata.-class mammals of sub class Metatheria(kangaroo) and sub class eutheria (monkey).
Correct answer is option A.

Correct answer is B.
As we go higher form species to kingdom, number of common characteristics goes on decreasing.

B is the right answer.
Musca domestica --- is Housefly. Phylum Arthropoda.

Linnaeus published his work on plant classification, specifically the sexual system of classification, in 'Species Plantarum' in 1753.

Agave and Yucca were moved to Agavaceae primarily due to their anatomical similarities, specifically in their vascular structure and leaf morphology.

Linnaeus's system was artificial because it relied on a few easily observable morphological characters, such as the number of stamens, rather than evolutionary or phylogenetic relationships.

In Whittaker's five kingdom system of classification, only kingdom Plantae have organisms with a multicellular eukaryotic organism with holophytic nutrition. The organisms which are able to synthesize food by photosynthesis are said to have holophytic nutrition. 

Monera is the most primitive kingdom mentioned by R.H.Whittaker. It is not well defined among all five kingdoms- Monera, Protista, Fungi, Plants, and Animalia.

The two kingdom classification system was given by Carlous Linnaeus in 1758, who classified living things into two kingdoms: Animal Kingdom (mobile and heterotrophic) and Plant Kingdom (fixed, stationary in the soil, autotrophic). These were then divided into classes and the classes into phyla for animals and divisions for plants. R.H Whittaker proposed the five kingdom classification in 1969, in which all living organisms are divided into five kingdoms based on their complexity of cell structure, complexity of organism’s body and mode of nutrition. The five kingdoms are Monera (prokaryotic BGA and bacteria), Protista (Eukaryotic unicellular organisms; algae and protozoa), Fungi, Plantae and Animalia. The four kingdom classification concept was given by Haeckel who divided living organisms into four kingdoms namely Monera, Protista, Metaphyta and Animalia. BGA and bacteria differ in their kind or reserve food, mode of nutrition, movement and type of photosynthetic pigments. Thus, the correct answer is option C.

The five kingdom classification was proposed by R. H. Whittaker in the year 1969. The kingdom Monera is comprised of unicellular prokaryotic organisms. This group contains the bacteria and the cyanobacteria species. The other four kingdoms, protista, fungi, plantae and animalia are composed of all the eukaryotic organisms. 

R.H.Whittaker was an American plant ecologist who proposed five kingdom scheme. J.B.S.Haldane was a British Indian scientist renowned for his innovative contributions in statistics and biostatics. George Gaylord Simpson was a palaeontologist. Ernst Mayr was a biologist.

The correct answer is D. 

Robert H. Whittaker in 1969, proposed five kingdom system of classification of organisms. The following three criteria were used for classification:

The Kingdom Protista (often including bacteria in older classifications) has boundaries that are not well defined because it contains diverse organisms that do not fit neatly into other kingdoms.

Human beings can move their limbs, jaws, eyelids, and ear pinna etc. These movements are referred to them by the presence of voluntary muscles and a framework of the body that allows Movement in such possible ways.

In biological classification, different orders are grouped into a single class because they share a set of fundamental, common characteristics.

A taxonomic key works by presenting a series of choices between two contrasting characters (couplets) to identify an organism.

Autotrophic organisms are those that can produce their own food using light (photosynthesis) or chemical energy.

Organisms of class: Cyclostomata belongs to division: Agnatha. Their skin is soft smooth, containing unicellular mucous gland but no scales.

Five kingdom classification was given by R.H. Whittaker. Classification of viruses has always been difficult as they are said to be threshold of life. Thus viruses did not find any position in five kingdom classification.

First step is taxonomy is identification of the organism. Identification is the finding of correct name and place of an organism according to some approved system of classification.

According to Linnaeus' system, each species is given a unique, two-part name called a binomen. Each binomen consists of a genus and species epithet. The species is the basic unit of classification and the only 'natural' one.
Correct option is option A.

Viruses are considered to be acellular as they do not have a defined cell wall, cell membrane, nucleus or nucleoid, cytoplasm and cellular organelles. For this reason, they cannot perform their metabolic activities on their own and are obligately dependent on the host cell machinery. Therefore, they do not find a place in the five-kingdom classification system.