The formula for exponential population growth is :-
dt/dN = rN
dN/rN = dt
rN/dN = dt
dN/dt = rN
Annual migration does not occur in the case of:
Salmon
Siberian crane
Salamander
Arctic tern
The population dynamics of a species is basically regulated by
Climate
Food supply
Competition between and within the species
All of the above
In a lake that undergoes thermal stratification, blooms of phytoplankton tend to occur
before thermal stratification
after thermal stratification
at the onset of thermal stratification
at the mid-phase of thermal stratification
Commensalism is an association of two species in which
one live attached to the other without harming it
both organisms derive benefit from each other
one derived its nutrition from the other
none of the above
Some students, during a study, caught, marked and released 80 fishes in a pond. Later
100 fishes were caught at random. Among these 40 were found to be marked. What is
the approximate number of fishes in the pond?
50
100
200
4000
The sphere of living matter together with water, air and soil on the surface of earth is
called
atmosphere
hydrosphere
lithosphere
biosphere
Mutualism is found in
Hermit crab and sea anemone
Ox pecker and rhinoceros
Zoochlorellae and Hydra
E.coli and man.
July 11 is observed as:
World population day
No tobacco day
World environment day
World health day
Which one of the following is a matching pair of certain organism(s) and the kind of
association?
Shark and sucker fish - predation
Algae and fungi in lichens - mutualism
Orchids growing on trees - parasitism
Cuscuta (dodder) growing in other flowering plants - epiphytism
The Great Barrier Reef along the east coast of Australia can be categorised as
population
community
ecosystem
biome
If the Bengal Tiger becomes extinct
Hyenas and wolves will become scars
The wild areas will be safe for man and domestic animals
Its gene pool will be lost forever
The population of beautiful animals like deers will get stabilized.
Which one of the following correctly represents an organism and its ecological niche?
Vallisneria and pond
Desert locust (Schistocerca) and desert
Plant lice (aphids) and leaf
Vultures and dense forest
In an experiment, freshly hatched larvae of an insect (Khapra beetle) were reared on a basal diet ( complete diet without cholesterol) with increasing amounts of cholesterols. Results obtained are shown in the graph given in the table:
The graph indicates that
(2) Growth of Khapra beetle is directly proportional to cholesterol concentration
Cholesterol is an essential dietary requirement of Khapra beetle
(3) Cholesterol concentration of 2 ug/g is the optimum level.
Growth of Khapra beetle is inhibited when cholesterol concentration exceeds 5ug/g diet.
Two opposite forces operate in the growth and development of every population. One of them is related to the ability to reproduce at a given rate. The force opposite to it is called
Fecundity
Environmental resistances
Biotic control
Mortality
One of the major difficulties in the biological control of insect pest is that
the predator develops a preference for other diets and may itself become a pest
the predator does not always survive when transferred to a new environment
the method is less effective as compared with the use of insecticides
the practical difficulty of introducing the predator to specific areas.
The growth curve of bacterial population in lab is plotted against time. What will be the shape of graph?
Sigmoid
Hyperbolic
Ascending straight line
Descending straight line
What is the Greek word for ecology?
Ethology
(2) oikologia
Synecology
(4) Hexicology
Bacteria, fungi, lower plants survive in adverse conditions by:
diapause
suspended growth
migration
formation of thick-walled spores
What are labelled phases A, B and C in givensigmoidal growth curve? A B C
Lag Stationary Log
Log Lag Stationary
Lag Log Stationary
Monarch butterfly escapes from predators by
foul smell
bitter taste
colour combination
rough skin
Which is correctly labelled with respect to the given diagram?
B: Logistic curve
C: Carrying capacity
C: Exponential curve
A: Carrying capacity
Which of the following associations shows mutualism?
Fig and wasp
Barnacles on whale
Roundworms in human intestine
Orchids on mango tree
Match column I with column II and select the correct option from the codes given below.
Column I Column II
A. Commensalism (i) One inhibited other unaffected
B. Parasitism (ii) One benefited other unaffected
C. Mutualism (iii) Both are benefitted
D. Amensalism (iv) One benefitted other harmed
A-(iv), B-(ii), C-(iii), D-(i)
A-(iii), B-(iv), C-(ii), D-(i)
A-(ii), B-(iv), C-(iii), D-(i)
A-(ii), B-(iv), C-(i), D-(iii)
The process where a population inhibits the growth of other population without affecting itself is known as
Amensalism
Parasitism
Mutualism
Commensalism
Which of the following is not a factor that would limit the growth of a population?
Food shortage
Immigration
Disease
Famine
The graph shows two types of population growth curve. A is exponential and B is logistic.
Which one of the following growth model considered as more realistic one?
Exponential growth curve
Logistic growth curve
Both the growth curves
None of the above
In an area, a population with large size individuals having long life span, more parental care and slow development was present. The type of population growth curve will be:
S-shaped
J-shaped
Z-shaped
All of these
The plants which can withstand with narrow and broad range of temperature tolerance respectively are:
monothermal and stenothermal
stenothermal and monothermal
stenothermal and eurythermal
stenothermal and mesothermal
Resemblance of one organism with its surroundings for protection and hiding is
mimicry
predation
adaptation
camouflage
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