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

  • Mode of nutrition


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

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A senentary sea anemone gets attached to the shell lining of hermit crab. The association is 

  • ectoparasitism

  • symbiosis

  • commensalism

  • commensalism


C.

commensalism

This type of mutualisn to called protocooperation. In this type, the sea anemone grows on the back of the hermit crab.  It protects the crab with the help of its nematocysts. Ectoparasites live on the outside of host., e.g., Human body louse. In this interaction, the parasite gets the benefits at the expense of the host.

Commensalism is an association between organisms in which one or both the species are benefitted and neither species is harmed. In amensalism, one species is harmed whereas the other is unaffected. Predation parasitism and commensalism share a common characteristic, the interacting species live closely together.

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

  • Eptatretus

  • Myxine

  • Neomyxine

  • Neomyxine


D.

Neomyxine

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. 

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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

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


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. 

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The chitinous exoskeleton of arthropods is formed by the polymerisation of

  • Keratin sulphate and chondraitin sulphate

  • D-glucosamine

  • N-acetyl glucosamine

  • N-acetyl glucosamine


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. 

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