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Class 10 Class 12

The eyes of Octopus and eyes of cat show different patterns of structure, yet they perform a similar function. This is an example of 

  • homologous organs that have evolved due to convergent evolution

  • homologous organs that have evolved due to divergent evolution

  • analogous organs that have evolved due to convergent evolution

  • analogous organs that have evolved due to divergent evolution


C.

analogous organs that have evolved due to convergent evolution

The analogous organs are not anatomically similar structures through they perform similar structure though they perform similar functions, Hence, analogous structures are a result of convergent evolution different structures evolving for the same function and hence, having similarity.
Homologous organs developed along different due to adaptations to different needs. This is divergent evolution and the structures are homologous.

The analogous organs are not anatomically similar structures through they perform similar structure though they perform similar functions, Hence, analogous structures are a result of convergent evolution different structures evolving for the same function and hence, having similarity.
Homologous organs developed along different due to adaptations to different needs. This is divergent evolution and the structures are homologous.


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

  • ectoparasitism

  • symbiosis

  • commensalism

  • amensalism


B.

symbiosis

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.

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.


Which of the following features is not present in Periplaneta americana?

  • Indeterminate and radical cleavage during embryonic development

  • Exoskeleton composed of N-acetylglucosamine

  • Metamerically segmented body

  • Schizocoelom as body cavity


A.

Indeterminate and radical cleavage during embryonic development

Cockroach has determinate cleavage during emembryonic development and it develops into nymph, which is a fully developed cockroach.

Cockroach has determinate cleavage during emembryonic development and it develops into nymph, which is a fully developed cockroach.


Which one of the following characteristics is not shared by birds and mammals?

  • Breathing using lungs

  • Viviparity

  • Warm-blooded nature

  • Ossified endoskeleton


B.

Viviparity

Mammals are viviparous while birds are oviparous. 

Mammals are viviparous while birds are oviparous. 


Which of the following features is not present in the phylum-Arthropoda?

  • Metameric segmentation

  • Parapodia

  • Jointed appendages

  • Chitinous exoskeleton


B.

Parapodia

Parapodia are present in annelids.

Parapodia are present in annelids.