Multiple Choice QuestionsAssertion : In a food chain members of successive higher levels are fewer in number.
Reason : Number of organisms at any trophic level depends upon the availability of organisms which serve as food at the lower level.
If both Assertion and Reason are true and the reason is the correct explanation of the assertion
If both Assertion and Reason are true but the reason is not the correct explanation of the assertion
If Assertion is true statement but Reason is false
If both Assertion and Reason are false statements
A.
If both Assertion and Reason are true and the reason is the correct explanation of the assertion
In a food chain the number of animals and biomass at the lower trophic level is abundant. Successive links of carnivores decrease rapidly in number until there are very few carnivores at the top.
Enzyme and carbohydrates dominate in the digestive tract of
carnivores
omnivores
parasites
herbivores
D.
herbivores
A herbivore is an animal that gets its energy from eating plants and only plants. These animals eat more carbohydrate food, therefore enzyme carbohydrate dominates.
When a natural predator (living being) is applied on the other pathogen organism to control them, this process is called
biological control
genetic engineering
artificial control
confusion technique
A.
biological control
Biological control methods include using natural predators of pests, using resistant varieties, crop rotation etc.
The food chain starts from :
consumer
producer
decomposer
nitrogen fixation
B.
producer
Food chain initiates from producers. Transfer of food energy from producers takes place through a series of organisms, i.e herbivores to carnivores to decomposers with repeated eating and being eaten is known as food chain.
Producers utilise the radient energy of sun which is transformed to chemical energy during photosynthesis. Thus, green plants occupy first trophic level in any food chain.
July 11 is observed as:
World population day
No tobacco day
World environment day
World health day
A.
World population day
World Population Day is celebrated on 11th July.
No Tobacco Day is celebrated on 31st May.
World Environment Day is celebrated on 5th June.
World Health Day is celebrated on 7th April.
Biological Oxygen Demand (BOD) is a measure of
industrial wastes poured into water bodies
extent to which water is polluted with organic compounds
amount of carbon monoxide inseparably combined with haemoglobin
amount of oxygen needed by green plants during night
B.
extent to which water is polluted with organic compounds
To measure water pollution, BOD or Biological Oxygen Demand test is done. In this test, amount of oxygen sufficient to degrade waste organic matter by bacteria in a sample is measured. The more oxygen used up by the bacteria to degrade the organic matter in the sample, the greter the BOD would be.
The 10% energy transfer law of food chain was given by
Stanley
Weismann
Lindemann
Tansley
C.
Lindemann
Only about 10% of the energy is transferred from one trophic level to the next. This 10% law of energy transfer was proposed by Lindemann (1942).
Some students, during a study, caught, marked and released 80 fishes in a pond. Later 100 fishes were caught at random. Among these 40 were found to be marked. What is the approximate number of fishes in the pond?
50
100
200
4000
C.
200
According to Petersons Mark and Recapture Method, the population (P) is given by
P = m(r + u)/r
where m = number of marked fishes
r = number of marked fishes recaptured
u = number of unmarked fishes captured
Here, m = 80; r = 40; u = 100 - 40 = 60
Therefore, P =
P =
P = 200
As insecticides reach at higher trophic level in food chain their concentration :
increases
become irregular
remain constant
decreases
A.
increases
Toxic pesticides such as BHC and DDT etc., are not easily degraded and are long lasting in the environment. They show biological magnification or food chain concentration i.e. the continuous increase in concentration of a toxicant at successive trophic levels in a food chain.
The term 'ecosystem' was coined by :
E.P. Odum
A.G. Tansley
Carl Mobious
W. Clementus
B.
A.G. Tansley
The term 'ecosystem' was coined by A.G. Tansley in 1935 and defined it as "the system resulting from the integration of all the living and non living factors of environment".
