The most common means of morphological defense in plants against herbivory are:

1.	Spines	2.	Thick cuticle
3.	Thorns	4.	Slime

As a mechanism of defense against herbivory, Calotropis:
1. Has a large number of thorns
2. Secretes cardiac glycosides
3. Produces a neurotoxin, strychnine
4. Releases a hallucinogen

Nicotine, caffeine, quinine and opium produced by plants are actually:

Consider the given statements regarding competition amongst organisms:

The correct statement/s is/are:

In some shallow American lakes, unrelated visiting Flamingoes and resident fishes compete for the common food which is:

A process in which the fitness of one species is significantly lower in the presence of another species, is termed as :

Abingdon tortoise in Galapagos islands became extinct within a decade after goats were introduced on the island due to:
1. Habitat fragmentation
2. Better browsing efficiency of goats
3. Predator of goat attacking tortoise
4. Virus of goats parasitizing tortoise

The ‘Competitive Exclusion Principle’ was given by:

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:

“Competitive Exclusion Principle” may be true if: