Effect of Sewage on Water Bodies

Q. Find out what do the terms algal bloom and red-tides signify.

Q.

All the following are waterborne diseases except

1. Typhoid

2. Dysentery

3. Cancer

4. Amoebiasis

Q. State whether true or false:
Coliform bacteria are found in the small intestine of humans.

1. True
2. False

Q. The image below is an example of ___

1. Eutrophication
2. Water pollution due to oil spill
3. Water pollution due to sewage water
4. Algal bloom

Q.

An important function of the micronutrient, _______________ , is chlorophyll synthesis.

1. iron

2. sulfur

3. chlorine

4. boron

Q. Arrange the following options in ascending order of their BOD value:

(I) Sample of highly polluted pond water
(II) Sample of unpolluted pond water
(III) Distilled water

1. III - I - II
2. II - III - I
3. III - II - I
4. I - III- II

Q. Ingestion of few molluscs can be toxic to humans.

1. True
2. False

Q. How are saprophytic basidiomycetes are able to decompose plant matter ? (1 mark)

Q.

Dumping of large quantities of biodegradable pollutants in a stream, leads to undesirable growth of microorganisms and plankton. This phenomenon is called

___.

1. Oligotrophication

2. Eutrophication

3. Biological oxygen demand

4. Dissolved oxygen