Natality refers to:
1. Death rate
2. Birth rate
3. Number of individuals leaving the habitat
4. Number of individuals entering the habitat
1. | pre-reproductive individuals are more than reproductive individuals. |
2. | reproductive individuals are less than post-reproductive individuals. |
3. | reproductive and pre-reproductive individuals are equal in number. |
4. | pre-reproductive individuals are less than reproductive individuals. |
1. Commensalism
2. Mutualism
3. Parasitism
4. Amensalism
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:
1. | Ecological niche | 2. | Biotic community |
3. | Ecosystem | 4. | Population |
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:
1. | Interspecific competition. |
2. | Competition within closely related species. |
3. | Reduced feeding efficiency in one species due to the presence of interfering species. |
4. | Intraspecific competition. |
What type of human population is represented by the following age pyramid?
The table below gives the populations(in thousands) of ten species(A--J) in four areas (a-d) consisting of the number of habitats given within brackets against each. Study the table and answer the question as follows:
which area out of a to d shows maximum species diversity?
1. b
2. c
3. a
4. d