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? [2022]
Predation
Amensalism
Commensalism
Competition
(1)
In predation, only one species benefits and the other is harmed.
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. [2022]
0.1
10
1.0
zero
(1)
Death rate in the given population of Drosophila during given time interval is
Inspite of interspecific competition in nature, which mechanism the competing species might have evolved for their survival? [2021]
Predation
Resource partitioning
Competitive release
Mutualism
(2)
If two species compete for the same resource, they could avoid competition by choosing different times for feeding or different foraging patterns. This is called resource partitioning.
Amensalism can be represented as [2021]
Species A (+); Species B (0)
Species A (–); Species B (0)
Species A (+); Species B (+)
Species A (–); Species B (–)
(2)
Amensalism is an interaction in which one species is harmed and other is unaffected.
In the exponential growth equation , e represents [2021]
the base of geometric logarithms
the base of number logarithms
the base of exponential logarithms
the base of natural logarithms
(4)
In the exponential growth equation, . Here is base of natural logarithms (2.71828).
Which of the following is not an attribute of a population? [2020]
Sex ratio
Natality
Mortality
Species interaction
(4)
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 [2019]
character displacement
altruism
resource partitioning
competitive exclusion
Between which among the following, the relationship is not an example of commensalism? [2019]
Orchid and the tree on which it grows
Cattle Egret and grazing cattle
Sea Anemone and Clown fish
Female wasp and fig species
(4)
Female wasp and fig species is an example of mutualism.
Natality refers to [2018]
death rate
birth rate
number of individuals leaving the habitat
number of individuals entering a habitat
(2)
Natality refers to the number of births during a given period in the population that are added to the initial density. Death rate or mortality is the number of deaths in the population during a given time period. Immigration is the number of individuals entering a habitat. Emigration is the number of individuals of the population that left the habitat and had gone elsewhere during a time period.
Which one of the following plants shows a very close relationship with a species of moth, where none of the two can complete its life cycle without the other? [2018]
Hydrilla
Yucca
Banana
Viola
(2)
Yucca has an obligate mutualism with a species of moth, i.e., Pronuba. The only pollinator of this plant is the Yucca moth. The Yucca moth is likewise dependent upon the Yucca plant as Yucca moth caterpillars need to eat Yucca seed only or starve.
