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Class 10 Class 12

Five Kingdom system of classification suggested by RH Whittaker is not based on

  • presence or absence of a well-defined nucleus

  • mode of reproduction

  • Mode of nutrition

  • Complexity of body organisation


A.

presence or absence of a well-defined nucleus

RH Whittaker's classification is nor based on presence or absence of a well - defined nucleus. He gave five kingdom classification and used five criteria for delimiting kingdoms.

These are

both come under body organisation

(i) Complexity of cell structure

(ii) Complexity of body structure

(iii) Mode of nutrition

(iv) Ecological life cycle including mode of reproduction

(v)Phylogenetic relationship.

He divided organisms into five kingdoms as follows:

Kingdom  - Monera

Kingdom - Protista

Kingdom - Fungi

Kingdom - Plantae

Kingdom - Animalia

RH Whittaker's classification is nor based on presence or absence of a well - defined nucleus. He gave five kingdom classification and used five criteria for delimiting kingdoms.

These are

both come under body organisation

(i) Complexity of cell structure

(ii) Complexity of body structure

(iii) Mode of nutrition

(iv) Ecological life cycle including mode of reproduction

(v)Phylogenetic relationship.

He divided organisms into five kingdoms as follows:

Kingdom  - Monera

Kingdom - Protista

Kingdom - Fungi

Kingdom - Plantae

Kingdom - Animalia


A jawless fish, which lays eggs in fresh water and whose ammocoetes larvae after metamorphosis return to the ocean is:

  • Eptatretus

  • Myxine

  • Neomyxine

  • Petromyzon


D.

Petromyzon

Petromyzon(the lamprey) belongs to the section Agnatha of the sub-phylum-Vertebrata. They have long, greenish brown, cylindrical body with smooth scaleless, slimy skin, jawless mouth, etc. They lay eggs in freshwater but their ammocoete larvae(lower) after metamorphosis return to the ocean. 

Petromyzon(the lamprey) belongs to the section Agnatha of the sub-phylum-Vertebrata. They have long, greenish brown, cylindrical body with smooth scaleless, slimy skin, jawless mouth, etc. They lay eggs in freshwater but their ammocoete larvae(lower) after metamorphosis return to the ocean. 


The chitinous exoskeleton of arthropods is formed by the polymerisation of

  • Keratin sulphate and chondraitin sulphate

  • D-glucosamine

  • N-acetyl glucosamine

  • lipoglycans


C.

N-acetyl glucosamine

The chitinous exoskeleton of arthropods is formed by the polymerisation of N-acetyl glucosamine, which  is a derivative of glucose. It is also a characteristic component of the cell wall of fungi, the radulae of molluscs and the beaks and internal shells of cephalopods including squid and octopuses. 

The chitinous exoskeleton of arthropods is formed by the polymerisation of N-acetyl glucosamine, which  is a derivative of glucose. It is also a characteristic component of the cell wall of fungi, the radulae of molluscs and the beaks and internal shells of cephalopods including squid and octopuses. 


Body having meshwork of cells, internal cavities lined with food filtering flagellated cells and indirect development are the characteristic of phylum

  • Coelenterate

  • Porifera

  • Mollusca

  • Protozoa


B.

Porifera

In Porifera (sponges), bodies are asymmetrical. Body lacks tissues or organs, but from a meshwork of cells surrounding channels that open to the outside through pores, and that expand into internal cavities lined with food filtering flagellated cells (choanocytes).

In Porifera (sponges), bodies are asymmetrical. Body lacks tissues or organs, but from a meshwork of cells surrounding channels that open to the outside through pores, and that expand into internal cavities lined with food filtering flagellated cells (choanocytes).


Metagenesis refers to

  • Presence of different morphic forms

  • Alternation of generation between asexual and sexual phases of an organism

  • Occurrence of a drastic change in form during post-embyonic development

  • Presence of a segmented body and parthenogenetic mode of reproduction


B.

Alternation of generation between asexual and sexual phases of an organism

Metagenesis is an organisation refers to the reproduction characterised by the alteration of a sexual generation and a generation that reproduces asexually, i.e., alternation of generations. 

Metagenesis is an organisation refers to the reproduction characterised by the alteration of a sexual generation and a generation that reproduces asexually, i.e., alternation of generations.