When the population density reaches the carrying capacity, the logistic growth curve is said to be in:

1. Lag phase

2. A phase of acceleration

3. A phase of deceleration

4. Asymptote

In general, which of the following is not an adaptation seen in parasites in accordance with their life style?

1. Loss of unnecessary sense organs

2. Presence of adhesive organs

3. Low reproductive capacity

4. Loss of digestive system

Which type of animal tissue changes the diameter of a blood vessel?

(1) Epithelium

(2) Connective

(3) Muscle

(4) Neural

Organisms with very high intrinsic growth rates have:

1. Long generation times

2. Short generation times

3. No courtship behaviour

4. No carrying capacities

Intraspecific competition is strongest when the:

1. Species overlap in their distribution

2. Populations overlap in their ranges

3. Population is at its carrying capacity

4. Reproductive rate is at its maximum

Asymptote in a logistic growth curve is obtained, when

(1) The value of 'r' approaches zero

(2) K = N

(3) K > N

(4) K < N

Mycorrhizae are the example of

(1) fungistasis                 

(2) amensalism

(3) antibiosis                   

(4) mutualism

Which of the following is correct for r-selected species?

(1) Large number of progeny with small size

(2) Large number of progeny with large size

(3) Small number of progeny with small size

(4) Small number of progeny with large size

If '+' sign is assigned to beneficial interaction, '-' sign to detrimental and '0' sign to neutral interaction, then the population interaction represented by '+' '-' refers to

(1) Mutualism

(2) Amensalism

(3) Commensalism

(4) Parasitism

When does the growth rate of a population following the logistic model equal zero? The logistic model is given as dN/dt = rN(1-N/K)

(1) when N nears the carrying capacity of the habitat

(2) when N/K equals zero

(3) when death rate is greater than birth rate

(4) when N/K is exactly one