Page 176 - Science Class 06

v Accumula on of wastes in our
surroundings a racts flies, mosquitoes,
Aim : To show that biodegradable
rats, birds and micro organisms. These
wastes decompose while non-
organisms may spread diseases by
biodegradable wastes do not.
contamina ng food and water.
Method : Take a piece of paper and a
piece of polybag. Dig two holes side-by-
side about one feet deep. Put the paper
in one hole and polybag in other. Cover
the holes with soil. Mark both the holes
with chalk powder. Dig both the holes
again a er a week and take out both the

pieces of paper and polybag. You will
Heaps of garbage are the breeding ground for germs.
observe that the paper has been de-
composed while the piece of the polybag v Polythene bags are non-biodegradable.
is in the same condi on. This ac vity Therefore, their accumula on in the
environment is very harmful. Besides,
shows that paper is biodegradable and
animals, some mes, eat these polybags
polybag is non-biodegradable.
which may be fatal for them.

v Liquid wastes discharged from homes
contain soap, detergent, oil, excreta,
etc. If these wastes are discharged into

water bodies, the water of the water
bodies becomes polluted and make
harm to aqua c plants and animals.
Biodegradable Non-Biodegradable Effluent discharged into water bodies by
the industries is also very harmful for
aqua c life.
HARMFUL EFFECTS OF WASTE

ACCUMULATION v Harmful gases and smoke released by
motor vehicles and industries cause air
v Accumula on of wastes causes harm to pollu on which finally cause many

the environment which ul mately cause respiratory problems.
harm to our health.
v Accumula on of wastes in the environ-

ment destroy the beauty of our
1. Write important sources of food wastes.
surroundings.
2. Write any two microogranisms.
v Dumping of wastes on land also causes 3. Why are biodegradable wastes not
soil pollu on. This finally results in harmful for the environment?
infer lity of soil. 4. Write any three harmful effects of the
accumula on of wastes.

176 Science-6