171.

Assertion : All pathogens are parasites but all parasites are not pathogens.

Reason : Majority of the parasites confer benefits to the host.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false

• If both assertion and reason are false

Eugenics is the branch concerned with

• improving the quality of human race by symptomatic treatment of genetic diseases.

• improving the quality of human populations by the application of genetic principles

• improving the quality of human race by providing best suitable environment.

• none of the above

Which of the following statements is incorrect

• Lichen, an association of fungus and algae is an example of mutualism.
  
  

• Those epiphytes which use other plants for support only and not for water or food supply and are examples of commensalism.

• Sea-anemone on hermit-crab is an example of protocooperation.

• Mutualism, protoocoperation, commensalism cannot be included under symbiosis.

Assertion: Koel does not build nest for egg laying.

Reason: Koel lays its eggs in the nest of tailor bird.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is falsen

• If both assertion and reason are false.

Which part of the world has a high density of organism?

• Deciduous forests

• Grasslands

• Tropical rain forests

• Savannahs

Assertion : The age-sex structure of human population in countries like France and Germany gives a steep pyramid.

Reason : In countries like Sudan and India the population is increasing at a rapid rate.

• If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion

• If both Assertion and Reason are true but the Reason is not the correct explanation of the assertion

• If Assertion is true but Reason is false

• If both Assertion and Reason are false

Mr.X is eating curd/yoghurt. For this food intake in a food chain he should be considered as occupying

• first trophic leve

• second trophic level

• third trophic level

• fourth trophic level

Which one of the following is a matching pair of certain organism(s) and the kind of association?

• Shark and sucker fish - commensalism

• Algae and fungi in lichens - mutualism

• Orchids growing on trees - parasitism

• Cuscuta (dodder) growing in other flowering plants - epiphytism.

Photochemical smog formed in congested metropolitan cities mainly consists of:

• ozone, peroxyacetyl nitrate and NO_x

• smoke, peroxyacetyl nitrate and SO₂

• hydrocarbons, SO₂ and CO₂

• hydrocarbons, ozone and SO_x

Assertion : Inhabitants close to very busy airports are likely to experience health hazards.

Reason : Sound level of jet aeroplanes usually exceeds 160 dB.

• If both Assertion and Reason are true and the reason is the correct explanation of the assertion

• If both Assertion and Reason are true but the reason is not the correct explanation of the assertion

• If Assertion is true statement but Reason is false

• If both Assertion and Reason are false statements