[PPSC PRINCIPAL, ITI (WOMEN) 2024]
16. Common indicator organism of water pollution is:
Platypus
E. coli
Pygmy hog
Indian Star Tortoise
17. What is the name of a species that is highly connected to the entire food web and whose loss may result in ecosystem collapse?
Ecotone species
Keystone species
Endemic species
Endagered species
18. Silviculture is the management of
Rivers
Lakes
Hills
Forests
19. Which of the following lines of evidence do geologists and climatologists follow to gain insights into the earth's climate history? 1. Examining the widths of tree rings 2. Analysing remains of plants, pollen, or microscopic organisms in lake beds and marine mud. 3. Studying fossils and rock types to infer what the climate must have been like. 4. Examining tiny air bubbles entrapped into ice
Choose the most appropriate answer from the options given below
1, 2, 3, 4
2 and 3 only
1 and 4 only
3 and 4 only
20. Consider the following two statements:
Statement I: Tropospheric ozone provides a critical protective shield against UV rays
Statement II: Stratospheric ozone is the major cause of smog and irritation in living tissues at the ground
In the light of the above statements, choose the most appropriate answer from the options given below
Both Statement I and Statement II are correct
Both Statement I and Statement II are incorrect
Statement I is correct but Statement II is incorrect
Statement I is incorrect but Statement II is correct