Organisms and Populations

In the light of the above statements, choose the correct answer from the options given below

1. (A) is false but (R) is true
2. Both (A) and (R) are true and (R) is the correct explanation of (A)
3. Both (A) and (R) are true but (R) is not the correct explanation of (A)
4. (A) is true but (R) is false

Secondary metabolites such as nicotine, strychnine and caffeine are produced by plants for their

1. Nutritive value
2. Growth response
3. Effect on reproduction
4. Defence action

Which of the following is not an attribute of a population?

1. Natality
2. Sex ratio
3. Mortality
4. Species interaction

Niche is

1. all the biological factors in the organism’s environment
2. the physical space where an organism lives
3. the range of temperature that the organism needs to live
4. the functional role played by the organism where it lives

Which one of the following population interactions is widely used in medical science for the production of antibiotics?

1. Commensalism
2. Mutualism
3. Parasitism
4. Amensalism

Natality refers to

1. death rate
2. birth rate
3. number of individuals leaving the habitat
4. number of individuals entering a habitat

In a growing population of a country,

1. pre-reproductive individuals are more than the reproductive individuals
2. reproductive individuals are less than the post-reproductive individuals
3. reproductive and pre-reproductive individuals are equal in number
4. pre-reproductive individuals are less than the reproductive individuals.

Asymptote in a logistic growth curve is obtained when :

1. K > N
2. The value of 'r' approaches zero
3. K < N
4. K = N

Plants which produce characteristic pneumatophores and show vivipary belong to :

1. Halophytes
2. Psammophytes
3. Hydrophytes
4. Mesophytes

Mycorrhizae are the example of :

1. Fungistasis
2. Antibiosis
3. Mutualism
4. Amensalism