1. The allochthonous microorganisms of an ecosystem are
(A) Indigenous microorganisms
(B) Migrant
(C) Parasitic
(D) Pathogenic



2. The biodegradation of plant material is slow because of presence of
(A) Cellulose
(B) Xylene
(C) Extensin/protein
(D) Lignin



3. An ecotype is
(A) Genetically different forms of the same organisms
(B) Genetically similar forms of the same organisms
(C) Morphologically different forms of the same organisms
(D) Both (A) and (B)


4. The following are the characters of species diversity:
(i) More richness
(ii) More evenness
(iii) More dominance
(iv) Less dominance
(v) Less richness
(vi) Less evenness

Point out the combination of conditions in which species diversity of an ecosystem will be more.
(A) (i), (ii) and (iii)
(B) (v), (ii) and (iii)
(C) (i), (ii) and (iv)
(D) (i), (vi) and (iv)


5. Given below are two statements, one labelled as Assertion (A) and the other labelled as Reason (R).
Assertion (A): If natality is greater than mortality, it leads to population explosion.
Reason (R): The scientific study of various species of human population is called demography.
Choose the correct answer:
(A) Both (A) and (R) are true and (R) is the correct explanation of (A).
(B) Both (A) and (R) are true, but (R) is not the correct explanation of (A).
(C) (A) is true, but (R) is false.
(D) Both (A) and (R) are false.



6. Match Column – I with Column – II :
Column – I                                          Column – II
(i) Chipko  Movement                         1. Medha Patkar
(ii) Narmada Bacchao Andolan          2. Al Gore
(iii) Climate Change                            3. Rachel Carson
(iv) Silent Spring                                 4. Sundarlal Bahuguna

Choose the correct code:
      (i) (ii) (iii) (iv)
(A) 1   2    3     4
(B) 2   3    4     1
(C) 4   1    2     3
(D) 3   4    1     2



7. Assertion (A): The energy flow in an ecosystem follows the law of thermodynamics.
Reason (R): The energy flow in an ecosystem is unidirectional and during the transformation of energy from one trophic level to the other, 80 – 90% of energy is lost.
Codes:
(A) Both (A) and (R) are true and (R) is the correct explanation of (A).
(B) Both (A) and (R) are true, but (R) is not the correct explanation of (A).
(C) (A) is true, but (R) is false.
(D) (A) is false, but (R) is true.


8. Assertion (A): Marine biodiversity tends to be highest in mid-latitudes in all oceans and along coasts in the Western Pacific.
Reason (R): Sea surface temperature along coasts in the Western Pacific is highest.
Codes:
(A) Both (A) and (R) are true and (R) is the correct explanation of (A).
(B) Both (A) and (R) are true, but (R) is not the correct explanation of (A).
(C) (A) is true, but (R) is false.
(D) (A) is false, but (R) is true.


9. “Double digging” is a method of
(A) Bio-intensive agriculture
(B) Deforestation
(C) Aforestation
(D) Water conservation


10. The rate of replacement of species along a gradient of habitats pertains to
(A) Alpha diversity
(B) Beta diversity
(C) Gamma diversity
(D) Species diversity


11. Match the List – I and List – II. Choose the correct answer from the given codes:
List – I                                    List – II
(Vegetation development)      (Nomenclature of succession)
(a) On a rock                         i. Psammosere
(b) On sand                           ii. Lithosere
(c) In aquatic habitat            iii. Xerosere
(d) In dry habitat                  iv. Hydrosere

 Codes:
(a)        (b)        (c)        (d)
(A)       ii          i           iv         iii
(B)       i           ii          iii         iv
(C)       iii         iv         ii          i
(D)       iv         iii         i           ii


12. If individuals of a species remain alive only in captivity or other human controlled conditions, the species is said to be
(A) Ecologically extinct
(B) Mass extinct
(C) Wild extinct
(D) Anthropogenic extinct


13. Which of the following symbolises correct sequence in hydrosere?
(A) Diatoms → Wolffia → Hydrilla → Cyperus → Populus
(B) Hydrilla → Wolffia → Cyperus → Populus → Diatoms
(C) Cyperus → Diatoms → Hydrilla → Wolffia → Populus
(D) Diatoms → Hydrilla → Wolffia → Cyperus → Populus


14. Which of the following is not a class of aquatic ecosystems based on salinity levels?
(A) Stagnant water ecosystem
(B) Freshwater ecosystem
(C) Brackish ecosystem
(D) Marine ecosystem


15. The K-strategists are
(a) Large organisms which have relatively longer life
(b) Provide care for their offsprings
(c) Organisms that stabilise their population at carrying capacity for the area

Choose the correct answer;
(A) (a) and (b) only
(B) (a) and (c) only
(C) (b) and (c) only
(D) (a), (b) and (c)