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 cholesterols. Results obtained are shown in the graph given in the table:

The graph indicates that

 

(1) Cholesterol is an essential dietary requirement of Khapra beetle

(2) Growth of Khapra beetle is directly proportional to cholesterol concentration

(3) Cholesterol concentration of 2 ug/g is the optimum level.

(4) Growth of Khapra beetle is inhibited when cholesterol concentration exceeds 5ug/g diet.

Two opposite forces operate in the growth and development of every population. One of them is related to the ability to reproduce at a given rate. The force opposite to it is called

(1) Fecundity

(2) Environmental resistances

(3) Biotic control

(4) Mortality 

One of the major difficulties in the biological control of insect pest is that

(1) the predator develops a preference for other diets and may itself become a pest

(2) the predator does not always survive when transferred to a new environment

(3) the method is less effective as compared with the use of insecticides

(4) the practical difficulty of introducing the predator to specific areas.

Which of the following statements is incorrect?

(1) Lichen, an association of fungus and algae is an example of mutualism

(2) Those epiphytes which use other plants for support only and not for water or food supply and are examples of commensalism.

(3) Sea-anemone on hermit-crab is an example of protocooperation

(4) Mutualism, protocooperation, commensalism cannot be included under symbiosis.

The growth curve of bacterial population in lab is plotted against time. What will be the shape of graph?

(1) Sigmoid

(2) Hyperbolic

(3) Ascending straight line

(4) Descending straight line

What is the Greek word for ecology?

(1) Ethology                     

(2) oikologia

(3) Synecology                 

(4)  Hexicology

Bacteria, fungi, lower plants survive in adverse conditions by:

(1) diapause                           

(2) suspended growth

(3) migration                         

(4) formation of thick-walled spores

What are labelled phases A, B and C in given
sigmoidal growth curve?


          A                 B                C
(1) Stationary      Log              Lag

(2) Lag                Stationary    Log

(3) Log                Lag              Stationary

(4) Lag                Log              Stationary

Monarch butterfly escapes from predators by

(1) foul smell                     

(2) bitter taste

(3) colour combination         

(4) rough skin

Which is correctly labelled with respect to the given diagram?

(1) B: Logistic curve

(2) C: Carrying capacity

(3) C: Exponential curve

(4) A: Carrying capacity