Between which of the following, the relationship is not an example of commensalism?

1. Orchid and the tree on which it grows

2. Cattle Egret and grazing cattle

3. Sea Anemone and Clownfish

4. Female wasp and fig species

Carnivorous animals - lions and leopards, occupy the same niche but lions predate mostly larger animals and leopards take smaller ones. This mechanism of competition is referred to as:

1. Character displacement

2. Altruism

3. Resource partitioning

4. Competitive exclusion

Which two of the following changes (a-d) usually tend to occur in the plain dwellers when they move to high altitudes? (3,500 m or more)
(a) Increase in red blood cell size
(b) Increase in red blood cell production
(c) Increased breathing rate
(d) Increase in thrombocyte count
Changes occurring are:
1. (a) and (d)
2. (a) and (b)
3. (b) and (c)
4. (c) and (d)

Predation and parasitism are which type of interactions?

1. (+, +)

2. (+, O)

3. (-, -)

4. (+, -)

Benthic organisms are found in:

1. Surface of marine water

2. Middle of water in sea

3. Bottom of sea

4. On-ground

Overlapping region between two ecosystems is called:

1. Biome

2. ecotone

3. Niche

4. Photic zone

Biotic potential or potential natality means:

1. Natural increase of population under ideal/optimum conditions

2. Potential of organisms in a biome

3. Number of organisms in a biome

4. Species of maximum number in a population

Zero growth means:

1. natality balance mortality

2. natality is more than mortality

3. natality is less than mortality

4. natality is zero

If the mean and the median pertaining to a certain character of a population are of the same value, the following is most likely to occur:

1. a normal distribution

2. a bi-modal distribution

3. a T-shaped curve

4. a skewed curve

The population of an insect species shows an explosive increase in numbers during the rainy season followed by its disappearance at the end of the season. What does this show?