Tag: zoology

Quizzes (289) Questions (5869)

Questions Related to zoology

Multiple choice zoology soil pollution industrial chemicals and their harmful effects toxic wastes and their effects soil pollution-causes

Which of the following is a cholinesterase inhibitor?

  1. Aldrin

  2. Malathion

  3. Endosulfan
  4. $\beta$-hexachlorocyclohexane
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Malathion is an organophosphate parasympathomimetic, which binds irreversibly to cholinesterase. Malathion is an insecticide of relatively low human toxicity. Malathion is a parasympathomimetic organophosphate compound that is used as an insecticide for the treatment of head lice. It inhibits acetylcholinesterase activity of most eukaryotes. Malathion is toxic to aquatic organisms, but has a relatively low toxicity for birds and mammals. 

Cholinesterases catalyze the hydrolysis of the neurotransmitter acetylcholine into choline and acetic acid, a reaction necessary to allow a cholinergic neuron to return to its resting state after activation. Because of its essential function, chemicals that interfere with the action of cholinesterase are potent neurotoxins, causing muscle spasms and ultimately death. Thus, the correct answer is option B.

Multiple choice zoology soil pollution industrial chemicals and their harmful effects toxic wastes and their effects soil pollution-causes

Bottom-feeding fish from the Great Lakes often contain

  1. Lead

  2. Dioxin

  3. Urethane

  4. Polychlorinated biphenyls

  5. B and D
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Polychlorinated biphenyls are a group of man-made chemicals useful in a variety of industrial processes, including the insulation and cooling of electrical equipment. But PCB pollution continues long after its source is cut off. PCBs are still found in the Great Lakes through a process called atmospheric deposition. Pollutants like dioxins and PCBs enter from the air into the water through rain and snow, falling particles, and absorption of the gas form of the pollutants into the water.  Dioxins are chemically similar to PCBs. Lake and river sediments are especially good at holding onto PCBs, so bottom-dwelling fish tend to have higher levels.

Therefore, the correct answer is option E.

Multiple choice zoology soil pollution industrial chemicals and their harmful effects toxic wastes and their effects soil pollution-causes

Which of the following is a herbicide?

  1. Allethrin

  2. Triazine

  3. Aldrin

  4. BHC
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The allethrins are a group of related synthetic compounds used in insecticides.

Triazine, is an important herbicide for quackgrass control and other perennial weeds. 
Aldrin is an organochlorine insecticide.
BHC is an organochloride.

Multiple choice zoology soil pollution industrial chemicals and their harmful effects toxic wastes and their effects soil pollution-causes

Atrazine is a

  1. Chemical pesticide

  2. Herbicide

  3. Fertlizer

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Atrazine, a triazine herbicide, is used in corn and sorghum for control of broadleaf weeds and grasses. Still used because of its low cost and because it works well on a broad spectrum of weeds common in the US corn belt, atrazine is commonly used with other herbicides to reduce the overall rate of atrazine and to lower the potential for groundwater contamination; it is a photosystem II inhibitor.

Multiple choice zoology soil pollution industrial chemicals and their harmful effects toxic wastes and their effects soil pollution-causes

Insecticides usually act upon

  1. Muscular system

  2. Digestive system

  3. Nervous system

  4. Circulatory system
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Insecticides based on their target sites and mode of action at the target sites can be classified into neurotoxins and others which do not target the nervous system of the insects. Insects have highly specialised interconnected cells nervous system along which electrical charge (impulse) travel. Neurotoxins target the enzymes involved in neurotransmission. The prolonged and irreversible disruption of a normal functioning nervous system may result in death.

So, the correct answer is 'Nervous system'

Multiple choice zoology soil pollution industrial chemicals and their harmful effects toxic wastes and their effects soil pollution-causes

Which one of the following is correct?

  1. Herbicides kill plants by blocking PS II

  2. Insecticides kill insects through impairment of nerve conduction and sometimes respiratory arrest

  3. Both A and B

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Herbicides of photosystem-II inhibit the reduction of plastoquinone at the secondary quinone acceptor site and its subsequent re-oxidation. This consequently light induces charge separation which leads to recombination processes. This process generates reactive oxygen species causing extensive damage in PS II and eventually kills the plant.

 Insecticides, on the other hand,  prevent tiny electric pulses to move to from one neuron to another forming synapse or they open sodium ion channels in neuron causing them to fire spontaneously where insect go into spasm and die.
Hence, the correct answer is 'Both A and B'.

Multiple choice zoology soil pollution industrial chemicals and their harmful effects toxic wastes and their effects soil pollution-causes

Now-a-days use of DDT as insecticide is banned because

  1. It is less effective than other pesticides

  2. Organisms develop resistance to it

  3. Production cost is very high

  4. It has long residual effect
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Dichlorodiphenyltrichloroethane, commonly known as DDT, is a colourless, tasteless, and an almost odourless crystalline chemical compound, an organochlorine, originally developed as an insecticide, and ultimately becoming infamous for its environmental impacts. Opposition to DDT was focused by the 1962 publication of Rachel Carson's book Silent Spring. It catalogued environmental impacts that coincided with the widespread use of DDT in agriculture in the United States, and it questioned the logic of broadcasting potentially dangerous chemicals into the environment leaving the residues for a long time.

So the correct answer is 'It has a long residual effect'.

Multiple choice zoology soil pollution industrial chemicals and their harmful effects toxic wastes and their effects soil pollution-causes

When EDTA solution added to ${ Mg }^{ 2+ }$ ion solution, then which of the following statement is not true?

  1. Four coordinates sites of ${ Mg }^{ 2+ }$ are occupied by EDTA and remaining two sites are occupied by water molecules.
  2. All six coordinate sites of ${ Mg }^{ 2+ }$ are occupied

  3. pH of the solution is decreased
  4. Colorless $[{ Mg-EDTA }]^{ 2- }$ chelate is formed
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
When EDTA solution added to the Mg2+ion solution, all six coordinate sites of Mg2+ are occupied, and a colourless [Mg−EDTA]2− chelate is formed. This reaction also results in the lowering of the pH of the solution.
So, the correct answer is 'Four coordinates sites of Mg2+ are occupied by EDTA and remaining two sites are occupied by water molecules.'
Multiple choice zoology soil pollution industrial chemicals and their harmful effects toxic wastes and their effects soil pollution-causes

Which of the following weedicide can defoliate the complete forest?

  1. 2, 4-D

  2. ABA

  3. AMO 1618

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Weedicides or herbicides are weed killers or pesticides used to control weeds in agricultural farms. AMO 1618  or (2-isopropyl-5-methyl-4-trimethylammonium chloride)-phenyl-1-piperidine carboxylate is an  inhibitor of gibberellin biosynthesis which leads to retarded germination. Higher concentrations will lead to  reduced sensitivity of seeds.