Page 1 - 3- Home Assignment I (Obj & Subj)-Water; water pollution

SAI International School
Subject- Biology
Chapter- Natural Resources
Subtopic- Water; water pollution
Module- 31
Home Assignment – I

Objective (MCQ)

1. The ‘water pollution’ can be defined in several ways. Which of the following
statements does not give the correct definition?
(a) The addition of the undesirable substances to water bodies
(b) The removal of the desirable substances from water bodies
(c) A change in pressure of the water bodies
(d) A change in temperature of the water bodies
2. Eutrophication is the process in which dissolved oxygen in water is reduced due
to excessive growth of algae. This is the result of
(a) Change in temperature of water
(b) Extra loading of nutrients in water body
(c) Stratification of aquatic habitat
(d) Bioaccumulation in algae.
3. The water cycle in nature involves which of the following processes sequentially?
(a) Evaporation, precipitation and condensation.
(b) Precipitation, condensation and evaporation.
(c) Evaporation, condensation and precipitation.
(d) Condensation, evaporation and precipitation.
4 Signs of eutrophication of water bodies include.
(a) reduced oxygen demand
(b) rapid decomposition of organic matter.
(c) algal bloom.
(d) fluorosis.
5 The term "water-pollution" can be defined in several ways. Which of the following
statements does not give the correct definition?
(a) The addition of undesirable substances to water-bodies
(b) The removal of desirable substances from water-bodies
(c) A change in pressure of the water bodies
(d) A change in temperature of the water bodies
6 Rainfall patterns depend on
(a) the underground water table
(b) the number of water bodies in an area
(c) the density pattern of human population in an area
(d) the prevailing season in an area
7 Total earth’s surface covered by water is
(a) 75%
(b) 60%
(c) 85%
(d) 50%
8 One of the following processes is not a step involved in the water-cycle operating
in nature
(a) evaporation
(b) transpiration
(c) precipitation