Question

Biomagnification of DDT causes a decline in bird population by
(a)Disturbing calcium metabolism
(b)Thinning of eggshells
(c)Premature breaking of eggs
(d)All of the above

Answer 1

Biomagnification of DDT leads to a higher concentration of DDT at a higher trophic level, and a higher concentration of DDT in birds leads to a disruption of calcium metabolism. And shows its effects on eggs. In this way, DDT biomagnification leads to a decline in the population of birds.

Complete answer:
A crystalline, colourless and odourless compound that is used as an insecticide is dichlorodiphenyltrichloroethane or DDT. DDT is deposited in the bodies of fishes as rain from the fields enters the water bodies. When birds consume fish, it accumulates in the body of the birds and thus enters the food chain in this way. The concentration of DDT rises with each successive trophic step, and this is known as biomagnification. The high concentration of DDT interferes with the calcium metabolism of birds and induces eggshell thinning. Premature breakage. This causes the population to decrease.

Additional Information: Bald eagle and other bird populations collapsed as DDT thinned their eggs, killing their embryos. In the United States, the pesticide, believed to accumulate in food webs and remain in soil and river sediment, was banned in 1972.
Control, DDT fed and starved chicks studied the mechanism of DDT impaired calcium absorption. In the 3 groups, the metabolism of [3H] cholecalciferol was the same, but the DDT fed and starved chicks had less calcium-binding activity in the intestine than the control chicks. These findings indicate that the impaired absorption of calcium by DDT and the activity of intestinal calcium-binding can result from anorexia induced by DDT.
So, the correct answer is ‘all of the above’.

Note: Dichlorodiphenyltrichloroethane, generally referred to as DDT, is an organochlorine, a colourless, tasteless, and nearly odourless crystalline chemical compound. It was initially created as an insecticide and became notorious for its effects on the environment. In 1874, the Austrian chemist Othmar Zeidler first synthesised DDT.