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 the death rate is greater than the birth rate
4.	when N/K is exactly one

An association of individuals of different species living in the same habitat and having functional interactions is known as:

In which of the following interactions both partners are adversely affected?

Just as a person moves from Delhi to Shimla to escape the heat for the duration of hot summer, thousands of migratory birds from Siberia and other extremely cold northern regions move to:
1. Western Ghat
2. Meghalaya
3. Corbett National Park
4. Keoladeo National Park

A biologist studied the population of rats in a barn. He found that the average natality was 250, average mortality 240, immigration 20 and emigration 30. The net increase in population is:

1. 15

2. 05

3. zero

4. 10

According to Darwin, organic evolution is due to:

What type of human population is represented by the following age pyramid? 

  
1.  Stable population
2.  Declining population
3.  Expanding population
4.  Vanishing population

Study the four statements (a–d) given below and select the two correct ones out of them:

The two correct statements are:
1. a and d
2. a and b
3. b and c
4. c and d