Under a particular set of selection pressures, organisms evolve towards the most efficient:

1. Thermoregulation

2. Water conservation

3. Respiration

4. Reproduction strategy

When certain exotic species are introduced into a geographical area, they become invasive mainly because:

1. The invaded land has unlimited resources for the introduced species

2. The invaded land does not have its natural predator

3. The population of the introduced species in the invaded land is very low

4. Introduced species do not face any competition in the introduced land

In a field experiment, when all Pisaster starfish were removed from an enclosed intertidal area, the result was:

1. Increase in diversity of invertebrates

2. Extinction of many invertebrate species

3. Inability of the Pisaster to enter the area again

4. Replacement of Pisaster by other starfish

As a mechanism of defense against herbivory, Calotropis:

(1) Has large number of thorns

(2) Secretes cardiac glycosides

(3) Produces a neurotoxin, strychnine

(4) Releases a hallucinogen

A species whose distribution is restricted to a small geographical area because of the presence of a competitively superior species is found to expand its distributional range dramatically when the competing species is experimentally removed. This is called:

1. Competitive Exclusion

2. Competitive Release

3. Competitive Supremacy

4. Competitive Inclusion

Which of the following is not an ectoparasite?

1. Lice on humans

2. Copepods on marine fishes

3. Mistletoe on other plants

4. Female Anopheles on humans

To get pollinated by a bee, the Mediterranean Orchid, Ophrys, employs:

1. Sexual deceit

2. Pseudo-copulation

3. Reward in the form of Nectar

4. Place for laying eggs

The country with the given population pyramid is likely to have:

1. Low birth rate

2. High death rate

3. Declining population in future

4. More females than males

In a tide pool, 15 species of invertebrates were reduced to 8 after one species was removed. The removed species may be a:

1. Parasite                   

2. Mutualist

3. Top predator           

4. Herbivore

The logistic growth curve of animal population growth is more realistic than J shaped curve because:

1. Asexual mode of reproduction is rare in higher animals

2. Resources are finite and become limiting sooner or later.

3. Most animals are conformers rather than regulators

4. Abiotic factors affect animals more than plants