CBSE Class 12 Biology - MCQ and Online Tests - Unit 13 - Organisms and Populations

CBSE Class 12 Biology – MCQ and Online Tests – Unit 13 – Organisms and Populations

Every year CBSE conducts board exams for 12th standard. These exams are very competitive to all the students. So our website provides online tests for all the 12th subjects. These tests are also very effective and useful for those who preparing for competitive exams like NEET, JEE, CA etc. It can boost their preparation level and confidence level by attempting these chapter wise online tests.

These online tests are based on latest CBSE Class 12 syllabus. While attempting these our students can identify the weak lessons and continuously practice those lessons for attaining high marks. It also helps to revise the NCERT textbooks thoroughly.

 

CBSE Class 12 Biology – MCQ and Online Tests – Unit 13 – Organisms and Populations

Question 1.
Water holding capacity is maximum in:
(a) Clay
(b) Sand
(c) Silt
(d) Gravel

Answer

Answer: (a) Clay

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Question 2.
Submerged hydrophytes havedisseced leaves for:
(a) Decreasing surface area
(b) Increasing surface area
(c) Reducing effect pf water currents
(d) Increasing number of stomata

Answer

Answer: (c) Reducing effect pf water currents

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Question 3.
Animals undergo inactive stage during winters. It is called :
(a) Acclimatisation
(b) Hibernation
(c) Aestivation
(d) Adapatation

Answer

Answer: (b) Hibernation

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Question 4.
Animals have innate ability to escape from predation. Select the incorrect example:
(a) Colour change in Chameleon
(b) Enlargement of body by swallowing air in puffer fish
(c) Poison fangas of snakes
(d) Melaninin in moths

Answer

Answer: (c) Poison fangas of snakes

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Question 5.
Praying mantis is a good example of:
(a) Camouflage
(b) Mullarian mimicry
(c) Warning colouration
(d) Social insect

Answer

Answer: (a) Camouflage

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Question 6.
Niche overlap is:
(a) Mutualism between two species
(b) Active cooperation between two species
(c) Tjvo different parasites on same food
(d) Sharing resources between two species

Answer

Answer: (d) Sharing resources between two species

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Question 7.
Habitat together with functions of a species constitute its:
(a) Topography
(b) Trophic level
(c) Boundary
(d) Ecological niche

Answer

Answer: (d) Ecological niche

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Question 8.
Science linking heredity with environment is:
(a) Ecology
(b) Ecophysiology
(c) Genecology
(d) Genetics

Answer

Answer: (c) Genecology

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Question 9.
Ozone protects biosphere from high energetic:
(a) Infra-red rays
(b) Ultraviolet rays
(c) X-rays
(d) gamma rays

Answer

Answer: (b) Ultraviolet rays

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Question 10.
The maximum growth rate occurs in :
(a) Lag phase
(b) Exponential, phase
(c) Stationary phase
(d) Senescent phase

Answer

Answer: (b) Exponential, phase

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Question 11.
Plants growing in saline soil with high salt concentration are:
(a) Xerophytes
(b) Halophytes
(c) Heliophytes
(d) Hydrophytes

Answer

Answer: (b) Halophytes

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Question 12.
Avicennia, Rhizophora andAtriplex are:
(a) Xerophytes
(b) Halophytes
(c) Hydrophytes
(d) Mesophytes

Answer

Answer: (b) Halophytes

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Question 13.
Maximum amounts of humus occurs on:
(a) In lower most layer
(b) In upper layer
(c) In Middle layer
(d) Same everywhere

Answer

Answer: (b) In upper layer

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Question 14.
In which one of the following habitats, does the diurnal temperature of soil surface veiw most?
(a) Shrub land
(b) Forest
(c) Desert
(d) Grassland

Answer

Answer: (c) Desert

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Question 15.
Mycorrhiza is an example to:
(a) Decomposers
(b) Endoparasitism
(c) Symbiotic relationship
(d) Ectoparasitism

Answer

Answer: (c) Symbiotic relationship

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