Organisms and Populations

Choose the correct statements regarding population interactions between two species. Choose the correct answer from the options given below :

1. A and B only
2. B and E only
3. B, D and E only
4. A and D only

Which of the following equations depicts Verhulst-Pearl logistic population growth ?

1. dNdt=rN ( K-NK )
2. dNdt=rN ( KK-N )
3. dNdt=rN ( K-NN )
4. dNdt=rN ( K+NK )

Which one of the following is an appropriate example of sexual deceit?

1. Sea anemone and clown fish
2. Ophrys and bumblebee
3. Female wasp and fig
4. Cuckoo and crow

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). In the light of the above statements, choose the most appropriate answer from the options given below:

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

Consider a population of 10 million cells. Given the per-capita birth rate of 0.002 (per unit time) and the per-capita death rate of 0.002 (per unit time), the expected number of cells after 10 generations is .

1. 100 million
2. 1 million
3. 5 million
4. 10 million

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). In the light of the above statements, choose the most appropriate answer from the options given below:

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

Epiphytes that are growing on a mango branch are an example of which of the following?

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

Who is known as the father of Ecology in India?

1. Ram Udar
2. Birbal Sahni
3. S.R. Kashyap
4. Ramdeo Misra

Given below are two statements : In the light of the above statements, choose the most appropriate answer from the options given below:

1. Statement I is correct but statement II is incorrect
2. Statement I is incorrect but statement II is correct
3. Both statement I and statement II are correct
4. Both statement I and statement II are incorrect

Which one of the following equations represents the Verhulst-Pearl Logistic Growth of population?

1. dNdt = rN ( N-KN )
2. dNdt = N ( r-KK )
3. dNdt = r ( K-NK )
4. dNdt = rN ( K-NK )

The equation of Verhulst-Pearl logistic growth is dNdt = rN [ K-NK ]. From this equation, K indicates:

1. Intrinsic rate of natural increase
2. Biotic potential
3. Carrying capacity
4. Population density

Given below are two statements: In the light of the above statements, choose the correct answer from the options given below :

1. Both Statement I and Statement II are true.
2. Both Statement I and Statement II are false.
3. Statement I is true but Statement II is false.
4. Statement I is false but Statement II is true.

When will the population density increase, under special conditions? When the number of :

1. Deaths exceeds number of births and also number of emigrants equals number of immigrants.
2. Births plus number of immigrants equals number of deaths plus number of emigrants.
3. Births plus number of emigrants is more than the number of deaths plus number of immigrants.
4. Births plus number of immigrants is more than the sum of number of deaths and number of emigrants.

What do 'a' and 'b' represent in the following population growth curve? [figure]

1. ‘a’ represents exponential growth when resources are not limiting the growth; and ‘b’ represents logistic growth when resources are limiting the growth.
2. ‘a’ represents logistic growth when resources are not limiting the growth; ‘b’ represents exponential growth when resources are limiting the growth.
3. ‘a’ represents carrying capacity and ‘b’ shows logistic growth when resources are limiting the growth.
4. ‘a’ represents exponential growth when resources are not limiting the growth and ‘b’ shows carrying capacity.

Given below are two statements: In the light of the above statements, choose the correct answer from the options given below:

1. Both Statement I and Statement II are false.
2. Statement I is correct but Statement II is false.
3. Statement I is incorrect but Statement II is true.
4. Both Statement I and Statement II are true.

Which one of the following statements cannot be connected to Predation?

1. It helps in maintaining species diversity in a community
2. It might lead to extinction of a species
3. Both the interacting species are negatively impacted
4. It is necessitated by nature to maintain the ecological balance

While explaining interspecific interaction of population, (+) sign is assigned for beneficial interaction, (−) sign is assigned for detrimental interaction and (0) for neutral interaction. Which of the following interactions can be assigned (+) for one species and (−) for another species involved in the interaction?

1. Predation
2. Amensalism
3. Commensalism
4. Competition

If '8' Drosophila in a laboratory population of '80' died during a week, the death rate in the population is individuals per Drosophila per week.

1. 0.1
2. 10
3. 1.0
4. zero

Two butterfly species are competing for the same nectar of a flower in a garden. To survive and coexist together, they may avoid competition in the same garden by :

1. Predating on each other
2. Feeding at the same time
3. Choosing different foraging patterns
4. Increasing time spent on attacking each other

In spite of interspecific competition in nature, which mechanism the competing species might have evolved for their survival?

1. Predation
2. Resource partitioning
3. Competitive release
4. Mutualism

Amensalism can be represented as :

1. Species A (+); Species B (0)
2. Species A (-); Species B (0)
3. Species A (+); Species B (+)
4. Species A (-); Species B (-)

In the exponential growth equation Nt = N0ert, e represents

1. The base of geometric logarithms
2. The base of number logarithms
3. The base of exponential logarithms
4. The base of natural logarithms

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