Niche is:

1.	All the biological factors in the organism environment
2.	The physical space where an organism lives
3.	The range of temperature that the organism needs to live
4.	The functional role played by the organism where it lives

Natality refers to:
1. Death rate
2. Birth rate
3. Number of individuals leaving the habitat
4. Number of individuals entering the habitat

Presence of plants arranged into well-defined vertical layers depending on their height can be seen best in:

1. Tropical Rain Forest

2. Grassland

3. Temperate Forest

4. Tropical Savannah

The principle of competitive exclusion was stated by?

1. C. Darwin

2. G. F. Gause

3. MacArthur

4. Verhulst and Pearl

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

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