Question

Consider the following statements concerning
food chains
(i) removal of 80% tigers from an area resulted
in greatly increased growth of vegetation
(ii) removal of most of the carnivores resulted
in an increased population of deers
(iii) the length of food chains is generally limited
to 3-4 trophic levels due to energy loss
(iv) the length of food chains may vary from 2
to 8 trophic levels
Which two of the above statement are correct ?
(a) ii and iii (b) iii and iv
(b) i and iv (d) i and ii

Answer 1

Answer:

according to me a option is correct that is 2 and 3

Answer 2

Answer is option "a"

Explanation:

• 1st statement is incorrect as removal of tigers from an area will result in decreased growth of vegetation as this will increase the increase in the population of deer which consumers more plants and thereby decreased vegetation.
• 2nd statement is correct as removal of most of the carnivores will result in increased population of deer as there are no animals to kill them.
• 3rd statement is correct as length of food chains is generally limited to 3-4 trophic levels in order to reduce energy loss as energy is loss at each trophic level and therefore sufficient energy would not be reach if chain has more then 4 trophic levels.
• 4th statement is incorrect as length of food chains does not varies from 2-8 trophic levels, it generally reaches upto 3-4 trophic levels in order to minimize the loss of energy.
• Hence, the right answer is option a  "II & III".