Carbohydrates are a source of energy. When broken down, the body uses them to power all its functions.
Species diversity refers to the number of different species in an ecosystem or on the earth as a whole. This is the commonest way to measure biodiversity.
A. the population of higher trophic levels is greater than lower trophic levels
Answer:
Option (D)
Explanation:
In terms of chemistry, a catalyst is usually defined as the substance that is commonly used in a reaction in order to increase the rate of reaction, without getting consumed. It helps in the reduction of activation energy.
In the given case, the lever or a person can be considered as a catalyst because both of these will increase the efficiency (or rate) in removing the rock from the top of the perch. Thus, the lever or the human will remain the same after the removal of rock as a catalyst can be recovered after the reaction.
Therefore, the correct answer is option (D).
