Ecosystem

The second stage of hydrosere is occupied by plants like

1. Vallisneria
2. Typha
3. Azolla
4. Salix

Identify the likely organisms (a), (b), (c) and (d) in the food web shown below : [figure]

1. (a) deer, (b) rabbit, (c) frog, (d) rat
2. (a) squirrel, (b) cat, (c) rat, (d) pigeon
3. (a) dog, (b) squirrel, (c) bat, (d) deer
4. (a) rat, (b) dog, (c) tortoise, (d) crow

Which one of the following is not a gaseous biogeochemical cycle in ecosystem?

1. Sulphur cycle
2. Nitrogen cycle
3. Phosphorus cycle
4. Carbon cycle

Identify the possible link "A" in the following food chain: Plant insect frog "A" Eagle

1. Wolf
2. Rabbit
3. Cobra
4. Parrot

Given below is an imaginary pyramid of numbers. What could be one of the possibilities about certain organisms at some of the different levels? [figure]

1. Level PC is "rats" and level SC is "cats"
2. Level PP is "phytoplankton" in sea and "whale" on top level TC
3. Level PP is "pipal trees" and the level SC is "sheep"
4. Level PC is "insects" and level SC is "small insectivorous birds"

Which one of the following is not a functional unit of an ecosystem?

1. Energy flow
2. Decomposition
3. Productivity
4. Stratification

The upright pyramid of numbers is absent in

1. Pond
2. Grassland
3. Lake
4. Forest

Which one of the following animals may occupy more than one trophic level in the same ecosystem at the same time?

1. Lion
2. Frog
3. Goat
4. Sparrow

Both, hydrarch and xerarch successions lead to:

1. Xeric conditions
2. Excessive wet conditions
3. Highly dry conditions
4. Medium water conditions

The breakdown of detritus into smaller particles by earthworm is a process called

1. Fragmentation
2. Catabolism
3. Mineralisation
4. Humification