DDT stands for dichloro-diphenyl-trichloroethane. The first kind of synthetic/artificial insecticides came into use in the 1940s. The earlier usage of DDT include: a) Killing of malarial vectors, b) Combatting Typhus and other insect borne human diseases, c) As a pest control in crops d) as a pest control in garden, live stock production and even at homes.
The negative impact of DDT could be felt for the first time when the pests that were earlier killed by use of DDT have now become pesticides resistant. In the 1950s in USA, the regulatory measures were adopted to reduce the usage of DDTs as its effects as a pesticides were no more long significant and also it was creating detrimental physical and psychological impacts on the human and environment.
It was in 1972 that the U.S. Environmental Protection Agency cancelled the order for banning the usage of DDT based on the adverse impact it produced on the environment, human and other life forms. Since then continuous studies are being conducted to analyse the impact of DDTs. In some later years it was established that DDT is the cause of producing tumors in liver.
Some of the common negative impacts produced by DDT as per the U.S. Department of Agriculture :
a) The non destructive nature – DDT can not be destroyed and thus it remains persistent in the atmosphere
b) It attacks the tissues of living organisms especially the animals and humans ( fatty tissue)
c) It can penetrate the atmosphere to deeper extent.
Now as per the current stuation, The use of DDT is controlled and other alternatives of pest control organisms is being deduced. As per the treaty of Stockholm Convention on POPs (Persistent organic pollutants) , usage of DDT for malarial control is justified but it puts a restrictive use of DDT as pesticides in other areas.
Answer:
<h2>Have a common understanding in the classification of organisms</h2>
Explanation:
- Taxonomy plays an important role in the classification of organisms to study the organisms on the basis of their properties.
- Taxonomy is a branch of biological science that explains the identification, characterization, naming and classification of the organisms thus it is helpful to understand the different types of organisms that are present in the biosphere.
- Taxonomy makes the scientist come on one point about the unknown organisms according to morphology, anatomy, physiology and some other properties of the organisms.
- Thus a common understanding is generated among scientists of the world.
<span>The correct answer is B. Pulmonary. The answers C. Cerebral and D. Extremity, are baseless regarding this question; A. Systemic could be a good alternative, as the blood flows from the systemic to the pulmonary circulation in the right side of the heart; but the systemic circulation is in fact mostly handled in the left side of the heart, while the right side handles the pulmonary one. </span>
Well, first off we would have more unlimited power supply and we would be able to get it easier because, the sun can produce harmful RB rays, all we would need to do is process it through a machine that can make it into a nuclear radiation rod that could be put into every electrical thing on this planet. We can also kill every one with the fire of a missile, and we could wipe the electrical currents of a nation out in one go.
Answer:
I think when the earth was created it took a time. Then dinosaurs came. Then tey extinct because falling of asteroid on Earth.Then after a period of time the sea,mountains and other natural things were made again.
