Pheretima and its close relatives derive nourishment from:

1. Sugarcane roots

2. Decaying fallen leaves and soil organic matter

3. Soil insects

4. Small pieces of fresh fallen leaves of maize

Which one of the following statements is correct for secondary succession?

Stability of ecosystem depends upon:

1. Primary

2. Interchange between producers and consumers

3. Number of producers

4. Number of consumers

Intermediate community between pioneer and climax communities is called:

1. seral community

2. biotic community

3. temporary community

4. ecosure

Ten per cent law of energy transfer in a food chain is given by:

1. Schimper

2. Elton

3. Haeckel

4. Lindemann

Soil salinity is measured by:

1. Parameter

2. Calorimeter

3. Conductivity meter

4. Potometer

The ultimate source of energy for living beings is:

1. Sunlight

2. ATP

3. Fats

4. Carbohydrates

Which of the following species are restricted to an area?

1. Sympatric species

2. Sibling species

3. Allopatric species

4. Endemic species