Question

In an experiment freshly hatched larvae of an insect (Khapra beetle) were reared on a basal diet (complete diet without cholesterol) with increasing amounts of cholesterol. Results obtained are shown in the given graph.
The graph indicates

• A. Cholesterol is an essential dietary requirement of khapra beetle.
• B. Growth of khapra beetle is directly proportional to cholesterol concentration.
• C. Cholesterol concentration of 2 $\mu$g/g diet is the optimum level.
• D. Growth of khapra beetle is inhibited when cholesterol concentration exceeds 5 $\mu$g/g diet.

Answer 1

Answer: (A)

Cholesterol is an essential dietary requirement of khapra beetle.

Here, the graph shown is the sigmoidal curve, meaning the growth curve is following the normal pattern. Initially, there was the lag phase, where it adjusted to the environment of cholesterol and then it entered log phase, where Khapra beetle grew rapidly followed by the stationary phase. Thus, it means that cholesterol is essential dietary requirement for Khapra beetle. Hence, option A is the correct answer.