Environmental Studies · Biology

Pesticides and Pest Control

1,208 Questions

Pesticides and Pest Control focuses on the management of invasive species through chemical, biological, and cultural methods. It includes topics like integrated pest management, herbicide targets, and the ecological impacts of toxic chemicals. This subject is frequently tested in environmental science and agriculture exams.

Integrated Pest ManagementBiological Control AgentsHerbicide MechanismsChemical Pesticide ToxicityGenetic Pest ResistanceInvasive Species Management

Pesticides and Pest Control Questions

Multiple choice zoology our environment - our concern biomagnification the effects of human activities on ecosystems bioaccumulation and biomagnification

In a highly pesticide polluted pond, which of the following aquatic organisms will have the maximum amount of pesticide per gram of body mass?

  1. Lotus

  2. Fishes

  3. Spirogyra

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

Biomagnification is the process where the concentration of toxic compounds increases in the body of the organisms through the food chain. The organisms at the higher trophic level will have more concentration of the compounds. Here, fishes are at the highest trophic level, so they will accumulate maximum amount of pesticides. So, the correct answer is 'Fishes'.

Multiple choice zoology our environment - our concern biomagnification the effects of human activities on ecosystems bioaccumulation and biomagnification

Biomagnification of DDT in an aquatic food chain starting from water having a concentration of 0.003 ppm may go, in fish eating ...... up to 

  1. 2 ppm

  2. 25 ppm

  3. 50 ppm

  4. 100 ppm
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Biomagnification refers to increase in concentration of the toxicant at successive trophic levels. This happens because a toxic substance accumulated by an organism cannot be metabolised or excreted, and is thus passed on to the next higher trophic level. 

This phenomenon is well known for mercury and DDT. In this manner, the concentration of DDT is increased  at successive trophic levels; e.g., if it starts at 0.003 ppb (ppb = parts per billion) in water, it can ultimately reach 25 ppm (ppm = parts per million) in fish-eating birds, through biomagnification.

Multiple choice zoology our environment - our concern biomagnification the effects of human activities on ecosystems bioaccumulation and biomagnification

Maximum DDT is present in birds feeding on 

  1. Fishes

  2. Meat

  3. Insects

  4. Seeds
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A few toxic substances, often present in industrial wastewaters, can undergo biological magnification in the aquatic food chain. Biomagnification refers to increase in the concentration of the toxicant at successive trophic levels. This happens because a toxic substance accumulated by an organism cannot be metabolised or excreted, and is thus passed on to the next higher trophic level. This phenomenon is well known for mercury and DDT. The concentration of DDT is increased  at successive trophic levels. For example, if it starts at 0.003 ppb (ppb = parts per billion) in water, it can ultimately reach 25 ppm (ppm = parts per million) in fish-eating birds, through biomagnification. 

High concentrations of DDT disturb calcium metabolism in birds, which causes thinning of eggshell and their premature breaking, eventually causing a decline in bird populations. 

Multiple choice zoology our environment - our concern biomagnification the effects of human activities on ecosystems bioaccumulation and biomagnification

What is the consequence of the spray of pesticides in the environment which threatens the predators in the area?

  1. Global warming

  2. Eutrophication of lakes

  3. Depletion of the ozone layer

  4. Magnification in the food chain

  5. Acid rain
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Slow metabolism and excretion of pesticides causes their accumulation in fat tissues of organisms and is referred to as biomagnifications. It particularly affects the top consumers (predators) of that food chain due to the higher concentration of toxic compounds. Thus, the correct answer is D.
Multiple choice zoology our environment - our concern biomagnification the effects of human activities on ecosystems bioaccumulation and biomagnification

Concentration of DDT from lower to higher trophic level _________.

  1. Increases

  2. Decreases

  3. Increases or decreases

  4. Remains constant
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

DDT (Dichlorodiphenyltrichloroethane) is an organochlorinated compound that is stable in nature. It is highly soluble in the fats of the living organism and so, it shows persistence in the food chain. It is seen that the level of DDT increases as the food chain progresses. It means, the primary consumers will have more DDT concentration than the producers, the secondary consumers will have more than primary consumers and so on. The highest concentrations will be seen in the top carnivore. This is because the consumers at the successive trophic level consume more than the previous level to fulfil the energy requirements. Due to this, DDT keeps on accumulating in the successive trophic levels in higher concentrations. This process is called the biomagnification.

Hence, the correct answer is 'Increases'.

Multiple choice zoology our environment - our concern biomagnification the effects of human activities on ecosystems bioaccumulation and biomagnification

As it passes into food chain, the concentration of DDT

  1. Remains same

  2. Decreases

  3. Increases

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

DDT (Dichlorodiphenyltrichloroethane) is an organochlorinated compound that is stable in nature. It is highly soluble in the fats of the living organism and so, it shows persistence in the food chain. It is seen that the level of DDT increases as the food chain progresses. It means, the primary consumers will have more DDT concentration than the producers, the secondary consumers will have more than primary consumers and so on. The highest concentrations will be seen in the top carnivore. This is because the consumers at the successive trophic level consume more than the previous level to fulfil the energy requirements. Due to this, DDT keeps on accumulating in the successive trophic levels in higher concentrations. This process is called the biomagnification.

Hence, the correct answer is 'Increases'.

Multiple choice zoology our environment - our concern biomagnification the effects of human activities on ecosystems bioaccumulation and biomagnification

Biological magnification occurs in case of

  1. Organochlorine insecticides

  2. Organophosphate pesticides

  3. Plants and animals in ecosystem with abundant resources

  4. Photography
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

DDT (Dichlorodiphenyltrichloroethane) is basically an organochlorine pesticide/insecticide. It was originally used for insecticides to prevent the crop from being damaged by insects, rodent, weeds etc. but due to its harmful effect it has been globally banned by "Stockholm convention on Persistent organic pollutant, 2001". By its nature, it is insoluble in water and shows high solubility in the fat of animals. They do not degrade easily and accumulate within the body of the organism in fat deposited portion. Due to their ability to show the biomagnification.

Hence, the correct answer is 'Organochlorine insecticides'.

Multiple choice biology breeding and biotechnology method of plant breeding for crop improvement plant breeding for food production biotechnology

Most herbicide interfere with

  1. Water absorption

  2. Translocation of sugar

  3. Photolysis of water
  4. ${ CO } _{ 2 }$ absorption
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Herbicides, also commonly known as weed killers, are pesticides used to kill unwanted plants. Selective herbicides kill specific targets, while leaving the desired crop relatively unharmed. Some of these act by interfering with the growth of the weed and are often synthetic mimics of natural plant hormones. A large number of different herbicide classes inhibit photosynthesis by binding to the quinone-binding protein, D-1, to prevent photosynthetic electron transfer. Mostly they interfere with photolysis of water. Thus, option C is correct. Herbicides does not interfere with water absorption, translocation of sugar and CO$ _{2}$ absorption. Thus, other options are wrong.

Multiple choice zoology immunity phagocytosis cells in immune system immune system, its cells, mediators and antigens

What is true about Bt toxin ?

  1. The concerned Bacillus has antitoxins

  2. The inactive protoxin gets converted into active form in the insect gut

  3. Bt protein exists as active toxin in the Bacillus

  4. The activated toxin enters the ovaries of the pest to sterilize it and thus prevent its multiplication.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Bt toxin is produced by Bacillus thuringiensis as an inactive protoxin. It only becomes toxic when ingested by an insect, where the alkaline pH of the midgut activates it, leading to the destruction of the insect's gut lining.

Multiple choice evs whose forests? improved methods of agriculture cropping patterns food for all conservation of forest and wildlife wildlife deforestation and conservation

If pests and weeds are not controlled at proper time ______

  1. They can destruct the crops so much that most of the crop is lost

  2. They can destruct the crops so much that most of the crop is no effect

  3. They can destruct the crops so much that most of the crop is gain

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

If weeds and pests are not managed, they compete for resources and damage the crop, leading to significant yield loss.

Multiple choice evs whose forests? improved methods of agriculture cropping patterns food for all conservation of forest and wildlife wildlife deforestation and conservation

Herbicides are chemicals which control

  1. Insects

  2. Fungi

  3. Weeds

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

Herbicides are chemical which control weeds. These are also called as weedicides. Glufosinate ammonium is a broad spectrum herbicides. A 2,4-D (2,4-Dichlorophenoxyacetic acid) is a plant hormone that acts as herbicide. It kills the broadleaf weeds that harm the plants by causing uncontrolled growth in them.

Thus, the correct answer is option C.

Multiple choice evs whose forests? improved methods of agriculture cropping patterns food for all conservation of forest and wildlife wildlife deforestation and conservation

Which of the following chemical/s cannot be used as a weedicide?

  1. Dalapon

  2. Metachlor

  3. 2-4- Dichlorophenoxy-acetic acid.

  4. Colchicine
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
A.Dalapon - used as a weedicide
B.Metachlor - used as a weedicide
C.2-4-Dichlorophenoxy acetic acid - used as a weedicide and hormone.
D.Colchicine  - used as a mutagen . It is a mitotic poison, it inhibits spindle formation that results in polyploidy of a cell. This can be detrimental for the major crop. So it isn't used as a weedicide.
So, the correct option is 'Colchicine'.
Multiple choice evs whose forests? improved methods of agriculture cropping patterns food for all conservation of forest and wildlife wildlife deforestation and conservation

The growth of weeds can be controlled by

  1. Manual removal

  2. Irrigation

  3. Herbicides

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The growth of weeds can be controlled by the following methods:

(1) Coverings: In domestic gardens, methods of weed control include covering an area of ground with a material that creates a hostile environment for weed growth, known as a weed mat. Several layers of wet newspaper prevent light from reaching plants beneath, which kills them.
(2) Manual removal: Many gardeners still remove weeds by manually pulling them out of the ground, making sure to include the roots that would otherwise allow them to resprout.
(3) Irrigation: Drip irrigation involves bringing water directly to the roots of the desired plants, thereby limits weed's access to water.
(4) Biological pesticide: Vinegar kills the visible part of the weed. They will wrinkle and die the next day, although the root will still be in place to continue growing. 


Therefore, the correct answer is option D.

Multiple choice evs whose forests? improved methods of agriculture cropping patterns food for all conservation of forest and wildlife wildlife deforestation and conservation

Weeds, insects and diseases can be controlled by _____

  1. Use of pesticides

  2. Sprayed on crop plants

  3. Herbicides, insecticides and fungicides

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Integrated pest management involves using various methods, including chemical agents like herbicides, insecticides, and fungicides, to control weeds, insects, and diseases.

Multiple choice evs whose forests? improved methods of agriculture cropping patterns food for all conservation of forest and wildlife wildlife deforestation and conservation

Weeds can be removed by using

  1. Pesticides

  2. Weedicides

  3. Antibiotics

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

Weeds are the undesirable plants that are not cultivated. They are the plants at the wrong place. They compete with the crop for nutrients and space. Hence, they are harmful to the crop. These weeds can be controlled by using weedicides.