The sum total of all surroundings of a living organism, including natural forces and other living things, which provide conditions for development and growth as well as of danger and damage is called environment.
What happens when we add our waste to the environment or throw ?
When we add our waste to the environment some of them are broken down by the biological processes but rest persists for a long time.
What are the different types of waste materials?
Waste that are broken down by the biological processes are said to be biodegradable. These wastes are decomposed through the actions of fungi, bacteria and other living organisms and enrich soil fertility. Examples: Food refuse, tree leaves urine and faecal matter, ewage agricultural residue, paper, wood, cloth, cow-dung, etc
Waste that are not broken down by the biological processes are said to be non biodegradable. These substances are inert and simply persist in the environment for a long time or may harm the various members of the ecosystem. Example ; these includes DDT, insecticides, pesticides, mercury, lead, arsenic, aluminimum, plastics, polythene bags, glass, radioactive wastes.
What happens after we throw waste away them away?
Fungi, bacteria and other living organisms in the presence of temperature and sunlight act on waste and try to break down.
Why are some substances biodegradable and some non-biodegradable?
Some substances are biodegradable and some are non bio-degradable. This is because of the specific action of the enzymes produced by bacteria or decomposers. The enzymes can break down natural substances into non poisonous simpler substances but cannot act on man-made substances like plastics
What are the harmful effects of biodegradable substance?
1. This waste destroyed the natural beauty and surroundings become dirty.
2. Decomposition of these wastes results in the production of foul smell, which spreads to surroundings areas.
3. These wastes may also block the drains creating pools of waste which becomes the breeding sites of mosquitoes. The letter is carriers of diseases like malaria and dengue.
What are the harmful effects of non- biodegradable substance?
1. These wastes are very harmful. They enter the food chains and their concentration goes on increasing from one trophic level to the next. This leads to biological magnification and result in harmful effects in human beings and other animals.
2. Dumping these wastes affects the soil fertility and subsequently reduces the crop yield.
3. Non-biodegradable chock out the sewage system and pollute the soil.
4. Some of the non-biodegradable substances may toxic for the humans and produce various diseases.
Name some of the biodegradable plastics.
Polyhydroxyalkanoates (PHAs) like the poly-3-hydroxybutyrate (PHB), polyhydroxyvalerate (PHV) and polyhydroxyhexanoate (PHH) .
What are the differences between biodegradable and non-biodegradable wastes.
1. The wastes are broken down naturally by microbial action
2. Biodegradation forms harmless and nonpoisonous products.
3. They release raw materials back to nature.
4. They pollute the environment only when they are produced in quantity beyond the capacity of environment to degrade them.
5. Recycling is possible either naturally or through human efforts.
1. The wastes are not broken down by the microbes.
2. No such action is possible.
3. They do not release raw materials.
4. Non-biodegradable wastes pollute the environment even in small quantity.
5. Recycling is possible only through human efforts.
What is echo system?
Ecosystem is a structural and functional unit of the biosphere consisting of a community of living beings and the physical environment. For example: forests, ponds and lakes are natural ecosystems while gardens and crop-fields and aquarium are human made (Artificial) ecosystems.
What are the different types of echo system?
Natural ecosystems are grass land, a forest, a sea, a river, a desert, a mountain, a pond, a lake etc.
The desert, grass land and mountain represent the terrestrial ecosystem (land based ecosystem).
The ponds, rivers, lakes and sea represent the aquatic ecosystem (water- based ecosystem).
Man – made or artificial ecosystems are garden, crop fields, park aquarium, etc.
Why does aquarium have to be cleaned once in a while?
To remove fish wastes from the water because there are no bacteria and fungi to break-down the dead remains and waste products of organisms.
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