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
Which of the following associations shows mutualism?
(1) Fig and wasp
(2) Barnacles on whale
(3) Roundworms in human intestine
(4) Orchids on mango tree