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:
I'm pretty sure the answer is B
Explanation:
Answer:
A
Explanation:
The correct answer would be that <u>the availability of food resources for black mice and brown mice will decrease.</u>
<em>Since the food requirements of the black mice are the same as that of the invasive brown mice, the available food supply that used to be only for the black mice would now be shared by the two strains of mice. Hence, the available food for the two groups of mice will naturally decrease.</em>
There is no sufficient information to conclude that the population of tan mice will decrease, hence, option B is incorrect.
The black mice and tan mice have different food requirements going by the information available in the illustration, hence, both cannot compete for food resources. Option C is, therefore, incorrect. In the same vein, option D is incorrect because the tan mice have different food requirements from the brown mice.
<u>The only correct option is A.</u>
Yes, C4 is a process used by plants to survive in hot dry climates along with the CAM cycle. Hope this helps!
Monocots have <em>parallel veins in leaves </em>while dicots have <em>netted veins in leaves. </em>Usually, monocots only have <em>herbaceous</em> stems while dicot stems can either be <em>herbaceous or woody. </em>Examples of monocots are <em>corn, asparagus, and grasses</em>. Examples of dicots are <em>beans, peaches, and potatoes.</em>
