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.
The right answer is mitosis.
Mitosis refers to the chromosomal events of eukaryotic cell division. This is a nonsexual / asexual duplication (unlike meiosis).
It also refers to a very particular stage of the eukaryotic cell cycle, called the "cell cycle", which is the stage of duplication of each chromosome of the mother cell and of their equal distribution in each of the two daughter cells.
Mitosis allows the formation of two daughter cells strictly identical genetically to the mother cell.
Answer:
Exactly the same in all organisms.
Explanation:
All living organisms store their genetic information as DNA. The way in which the information is encoded is referred to as the GENETIC CODE. The genetic code comprises of all three nucleotides called CODON that encodea an amino acid in all organisms.
The genetic code is said to be UNIVERSAL i.e. the same genetic code is used by all known living organisms, as a codon does not specify another amino acid in another organism. It is universal in all organisms that AUG codon specifies Methionine. This universality of the genetic code further helps to show the shared ancestry between all organism.
