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All questions of Population Dynamics for Grade 12 Exam
Biological organisation starts witha) Cellular levelb) Atomic levelc) Submicroscopic molecular leveld) Organismic levelCorrect answer is option 'C'. Can you explain this answer?
|
Rohit Shah answered |
Correct option is (c)
Biological organisation starts with submicroscopic molecular level, where four types of molecules, i.e. carbohydrates, lipids, proteins and nucleic acid are organised into organelles of cell.
Biological organisation starts with submicroscopic molecular level, where four types of molecules, i.e. carbohydrates, lipids, proteins and nucleic acid are organised into organelles of cell.
Animals undergo an inactive stage during the winter known as- a)Adaptation
- b)Hibernation
- c)Aestivation
- d)Acclimatisation
Correct answer is option 'B'. Can you explain this answer?
Animals undergo an inactive stage during the winter known as
a)
Adaptation
b)
Hibernation
c)
Aestivation
d)
Acclimatisation
|
Vijay Bansal answered |
Aestivation: Aestivation is summer sleep and during aestivation, animals usually tend to rest in a shady and cool place. ... In aestivation, usually cold blooded animals like reptiles maintain their body temperature by reducing their metabolic activities and protecting themselves from very high temperature.
Organisms capable of maintaining constant body temperature are- a)Poikilothermal
- b)Conformers
- c)Stenothermal
- d)Homeothermal
Correct answer is option 'D'. Can you explain this answer?
Organisms capable of maintaining constant body temperature are
a)
Poikilothermal
b)
Conformers
c)
Stenothermal
d)
Homeothermal
|
Pooja Mehta answered |
Homeotherms: animals who maintain a constant internal body temperature across a wide range of environmental conditions. Most mammals and birds are homeotherms.
Which of the following is/are poikilotherm:?- a)Tapeworm and rabbits
- b)Elephants
- c)Humans and fishes
- d)Tapeworm and naked mole rat
Correct answer is option 'D'. Can you explain this answer?
Which of the following is/are poikilotherm:?
a)
Tapeworm and rabbits
b)
Elephants
c)
Humans and fishes
d)
Tapeworm and naked mole rat
|
Lavanya Menon answered |
- Poikilotherms or cold blooded animals are referred to as organisms that can change their body temperature according to the environment around.
- Tape worms and naked mole rats are examples of cold blooded animals.
Cold-blooded animals fall under the category of- a)Psychotherms
- b)Ectotherms
- c)Thermophiles
- d)Endotherms
Correct answer is option 'B'. Can you explain this answer?
Cold-blooded animals fall under the category of
a)
Psychotherms
b)
Ectotherms
c)
Thermophiles
d)
Endotherms
|
|
Priya Patel answered |
An ectotherm "outside" and "hot"), is an organism in which internal physiological sources of heat are of relatively small or quite negligible importance in controlling body temperature.] Such organisms (for example frogs) rely on environmental heat sources,which permit them to operate at very economical metabolic rates. Colloquially, some refer to these organisms as "cold blooded" though such a term is not technically correct, as the blood temperature of the organism varies with ambient environmental temperature. Some of these animals live in environments where temperatures are practically constant, as is typical of regions of the abyssal ocean and hence can be regarded as homeothermic ectotherms. In contrast, in places where temperature varies so widely as to limit the physiological activities of other kinds of ectotherms, many species habitually seek out external sources of heat or shelter from heat; for example, many reptiles regulate their body temperature by basking in the sun, or seeking shade when necessary in addition to a whole host of other behavioral thermoregulation mechanisms. For home captivity as pet, reptile owners can use a UVB/UVA light system to assist the animals' basking behaviour.
In which of the following interactions both partners are adversely affected ?[2015 RS]- a)Predation
- b)Parasitism
- c)Mutualism
- d)Competition
Correct answer is option 'D'. Can you explain this answer?
In which of the following interactions both partners are adversely affected ?
[2015 RS]
a)
Predation
b)
Parasitism
c)
Mutualism
d)
Competition
|
Priyanka Iyer answered |
(d) Competition occurs for light, food and space among organisms in which all partners are adversely affected in an ecosystom.
Xerophytes are mostly- a)Succulents
- b)Water related
- c)Mesophytes
- d)None of the above
Correct answer is option 'A'. Can you explain this answer?
Xerophytes are mostly
a)
Succulents
b)
Water related
c)
Mesophytes
d)
None of the above
|
|
Pooja Mehta answered |
Plants adapted to living in dry environments such as succulents are termed xerophytes. However, not all xerophytes are succulents, since there are other ways of adapting to a shortage of water, e.g., by developing small leaves which may roll up or having leathery rather than succulent leaves.
Orchid shows commensalism as interaction with:- a)bee
- b)mango tree
- c)both mango tree and bee
- d)none of these
Correct answer is option 'B'. Can you explain this answer?
Orchid shows commensalism as interaction with:
a)
bee
b)
mango tree
c)
both mango tree and bee
d)
none of these
|
Shivani Rane answered |
Commensalism is interaction in which one species is benefited by other is neither benefited nor harmed. Orchids growing on mango tree do not harm the mango plants but get shelter.
The birth and death rates of four counteries are given below. which one will have the least population growth rate?
- a)P
- b)Q
- c)R
- d)S
Correct answer is option 'D'. Can you explain this answer?
The birth and death rates of four counteries are given below. which one will have the least population growth rate?
a)
P
b)
Q
c)
R
d)
S
|
Suresh Iyer answered |
Growth rate = Birth rate - death rate
For country P, it is 10/1000. For country Q, It is 15/1000
For country R, it is 17/1000. For country S, It is 7/1000
Hence, country S has the least population growth rate
For country P, it is 10/1000. For country Q, It is 15/1000
For country R, it is 17/1000. For country S, It is 7/1000
Hence, country S has the least population growth rate
A statement 933 females per 1000 males depict:- a)ecological ages
- b)generation time
- c)sex ratio
- d)biotic potential
Correct answer is option 'C'. Can you explain this answer?
A statement 933 females per 1000 males depict:
a)
ecological ages
b)
generation time
c)
sex ratio
d)
biotic potential
|
Aman Sharma answered |
Sex ratio is the no of female available per thousands of male in a population. Sex ratio is decline due to female feticides alarmingly in some part of India.
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]- a)Character displacement
- b)Altruism
- c)Resource partitioning
- d)Competitive exclusion.
Correct answer is option 'C'. Can you explain this answer?
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]
a)
Character displacement
b)
Altruism
c)
Resource partitioning
d)
Competitive exclusion.
|
|
Vijay Bansal answered |
Species facing competition might evolve mechanism that promotes co-existence rather exclusion. One such mechanism is resource partitioning.
Resource partitioning is the division of limited resources by species to help avoid competition in an ecological niche. Example - carnivorous animals like lions, leopards occupy the same niche but lions predate mostly larger animals and leopards take smaller ones.
So, correct answer is option C.
Small fish get stuck near the bottom of a shark and derive their nutrition from it? This kind of association is called- a)Parasitism
- b)Symbiosis
- c)Predation
- d)Commensalism
Correct answer is option 'D'. Can you explain this answer?
Small fish get stuck near the bottom of a shark and derive their nutrition from it? This kind of association is called
a)
Parasitism
b)
Symbiosis
c)
Predation
d)
Commensalism
|
Sonal Chakraborty answered |
Commensalism is a type of symbiotic relationship where one species benefits from the association, while the other is neither harmed nor helped. In this type of association, one species derives benefits from the other without causing any harm to the host.
Explanation:
In the given scenario, the small fish gets stuck near the bottom of a shark and derives its nutrition from it. The small fish is not harming the shark, nor is it providing any benefits to the shark. Therefore, this is an example of commensalism.
The small fish is using the shark as a shelter and also gets access to food particles that are present near the shark's mouth. The shark is not affected by the presence of the small fish, and it does not derive any benefit from it either.
In summary, commensalism is a type of symbiotic relationship where one species benefits from the association, while the other is neither harmed nor helped. The small fish getting stuck near the bottom of a shark and deriving its nutrition from it is an example of commensalism.
Explanation:
In the given scenario, the small fish gets stuck near the bottom of a shark and derives its nutrition from it. The small fish is not harming the shark, nor is it providing any benefits to the shark. Therefore, this is an example of commensalism.
The small fish is using the shark as a shelter and also gets access to food particles that are present near the shark's mouth. The shark is not affected by the presence of the small fish, and it does not derive any benefit from it either.
In summary, commensalism is a type of symbiotic relationship where one species benefits from the association, while the other is neither harmed nor helped. The small fish getting stuck near the bottom of a shark and deriving its nutrition from it is an example of commensalism.
A large regional unit characterised by a major vegetation type and associated fauna found in a specific climate zone constitutes- a)Biological community
- b)Ecosystem
- c)Biome
- d)Habitat
Correct answer is option 'C'. Can you explain this answer?
A large regional unit characterised by a major vegetation type and associated fauna found in a specific climate zone constitutes
a)
Biological community
b)
Ecosystem
c)
Biome
d)
Habitat
|
Gaurav Kumar answered |
A biome is a community of plants and animals that have common characteristics for the environment they exist in. They can be found over a range of continents. Biomes are distinct biological communities that have formed in response to a shared physical climate."Biome" is a broader term than "habitat"; any biome can comprise a variety of habitats.
While a biome can cover large areas, a microbiome is a mix of organisms that coexist in a defined space on a much smaller scale. For example, the human microbiome is the collection of bacteria, viruses, and other microorganisms that are present on or in a human body.
A 'biota' is the total collection of organisms of a geographic region or a time period, from local geographic scales and instantaneous temporal scales all the way up to whole-planet and whole-timescale spatiotemporal scales. The biotas of the Earth make up the biosphere.
When does the growth rate of a population following the logistic model equal zero ? The logistic model is given as dN/dt = rN(1–N/K)[2016]- a)when N/K is exactly one.
- b)when N nears the carrying capacity of the habitat.
- c)when N/K equals zero.
- d)when death rate is greater than birth rate.
Correct answer is option 'A'. Can you explain this answer?
When does the growth rate of a population following the logistic model equal zero ? The logistic model is given as dN/dt = rN(1–N/K)
[2016]
a)
when N/K is exactly one.
b)
when N nears the carrying capacity of the habitat.
c)
when N/K equals zero.
d)
when death rate is greater than birth rate.
|
Pallabi Reddy answered |
Homeostasis is[1991]- a)tendency of biological systems to change with change in environment
- b)tendency of biological systems to resist change
- c)disturbance of self regulatory system and natural controls
- d)biotic materials used in homeopathic medicines.
Correct answer is option 'B'. Can you explain this answer?
Homeostasis is
[1991]
a)
tendency of biological systems to change with change in environment
b)
tendency of biological systems to resist change
c)
disturbance of self regulatory system and natural controls
d)
biotic materials used in homeopathic medicines.
|
Pankaj Kulkarni answered |
Homeostasis is the property of an open system, especially living organisms, to regulate its internal environment to maintain a stable, constant condition, by means of multiple dynamic equilibrium adjustments, controlled by interrelated regulation mechanisms.
Gause's principle of competitive exclusion states that :[2016]- a)more abundant species will exclude the less abundant species through competition.
- b)competition for the same resources excludes species having different food preferences.
- c)no two species can occupy the same niche indefinitely for the same limiting resources.
- d)larger organisms exclude smaller ones through competition.
Correct answer is option 'C'. Can you explain this answer?
Gause's principle of competitive exclusion states that :
[2016]
a)
more abundant species will exclude the less abundant species through competition.
b)
competition for the same resources excludes species having different food preferences.
c)
no two species can occupy the same niche indefinitely for the same limiting resources.
d)
larger organisms exclude smaller ones through competition.
|
|
Pallabi Reddy answered |
(c) Gause's principle of competitive exclusion can be restated to say that no two species can occupy the same niche indefinitely when resources are limiting. Certainly species can and do coexist while competing for some of the same resources. Nevertheless, Gause's theory predicts that when two species coexist on a long-term basis, either resources must not be limited or their niches will always differ in one or more features; otherwise, one species will outcompete the other and the extinction of the second species will inevitably result, a process referred to as competitive exclusion
Human population follows the- a)J-shaped growth curve
- b)Z-shaped growth curve
- c)S-shaped growth curve
- d)All of the above
Correct answer is option 'C'. Can you explain this answer?
Human population follows the
a)
J-shaped growth curve
b)
Z-shaped growth curve
c)
S-shaped growth curve
d)
All of the above
|
Harshitha Chavan answered |
Logarithmic or Exponential phase : It is characterized by rapid growth in population which continues till enough food is available. But with the increase in reindeer population, there is corresponding decrease in the availability of food and space, which finally become exhausted, which leads to mass starvation and mortality. This sudden increase in mortality is called population crash. Lemming of Tundra, some insect, algal blooms and annual plants also show J-shaped curves. The population growth curve is S- shaped in most of the organisms, Human population also shows S-shaped curve.
Cuscuta is an example of[2012M]- a)ectoparasitism
- b)brood parasitism
- c)predation
- d)endoparasitism
Correct answer is option 'A'. Can you explain this answer?
Cuscuta is an example of
[2012M]
a)
ectoparasitism
b)
brood parasitism
c)
predation
d)
endoparasitism
|
Mrinalini Bajaj answered |
Cuscuta, or Dodder plant, is a parasitic plant that wraps around other plants for nourishment. Cuscuta is found on outer side of the host and is total stem parasite. Cuscuta a parasite of Acacia.
Exponential growth pattern in a population results into:- a)Sigmoid curve
- b)U-shaped curve
- c)J-shaped curve
- d)None of these
Correct answer is option 'C'. Can you explain this answer?
Exponential growth pattern in a population results into:
a)
Sigmoid curve
b)
U-shaped curve
c)
J-shaped curve
d)
None of these
|
Shalini Saha answered |
Exponential growth pattern in population results into j-shaped curve. During exponential growth faster growth occurs and j-shaped curve is formed when time v/s growth is drawn.
The birth rate if 7 new plants are added to previous year plant population of 23 Salvinia plants will be:- a)0.3
- b)0.25
- c)0.4
- d)0.5
Correct answer is option 'A'. Can you explain this answer?
The birth rate if 7 new plants are added to previous year plant population of 23 Salvinia plants will be:
a)
0.3
b)
0.25
c)
0.4
d)
0.5
|
|
Wahid Khan answered |
The birth rate of a population = new individual added / previous population. Here birth rate= 7/23=0.3043. Hence, birth rate of Salvinia plants is equal to 0.3.###@
Interacting members of species live close to each other in following interaction/s:- a)parasitism
- b)competition
- c)commensalism, predation and parasitism
- d)commensalism
Correct answer is option 'C'. Can you explain this answer?
Interacting members of species live close to each other in following interaction/s:
a)
parasitism
b)
competition
c)
commensalism, predation and parasitism
d)
commensalism
|
Sushant Goyal answered |
Interacting members of species live close to each other in commensalism, predation and parasitism.
Mycorrhiza represents - a)symbiotic association between a fungus and liverworts
- b)parasitic association between a fungus and an alga
- c)parasitic association between a fungus and roots of plants
- d)symbiotic association between a fungus and roots of higher plants
Correct answer is option 'D'. Can you explain this answer?
Mycorrhiza represents
a)
symbiotic association between a fungus and liverworts
b)
parasitic association between a fungus and an alga
c)
parasitic association between a fungus and roots of plants
d)
symbiotic association between a fungus and roots of higher plants
|
Sonal Kulkarni answered |
A nutrient depletion zone can develop when there is rapid soil solution uptake, low nutrient concentration, low diffusion rate, or low soil moisture. These conditions are very common; therefore, most plants rely on fungi to facilitate the uptake of minerals from the soil. Mycorrhizae, known as root fungi, form symbiotic associations with plant roots. In these associations, the fungi are actually integrated into the physical structure of the root. The fungi colonize the living root tissue during active plant growth.
Species facing competition might evolve mechanism that promotes co-existence rather than exclusion and that mechanism can be- a)Interspecific competition
- b)Intraspecific competition
- c)Competitive release
- d)Resource partitioning
Correct answer is option 'D'. Can you explain this answer?
Species facing competition might evolve mechanism that promotes co-existence rather than exclusion and that mechanism can be
a)
Interspecific competition
b)
Intraspecific competition
c)
Competitive release
d)
Resource partitioning
|
Pooja Choudhary answered |
Species facing completion might evolve mechanism that promotes co-existence rather than exclusion that mechanism is called resource partitioning. In which they avoid completion by choosing different times of feeding or different foraging patterns.
A mutually beneficial association necessary for survival of both partners is[1988]- a)mutualism/symbiosis
- b)commensalism
- c)amensalism
- d)both A and B
Correct answer is option 'A'. Can you explain this answer?
A mutually beneficial association necessary for survival of both partners is
[1988]
a)
mutualism/symbiosis
b)
commensalism
c)
amensalism
d)
both A and B
|
Lekshmi Banerjee answered |
Symbiosis or mutualism is a mutually beneficial association necessary for the survival of both the partners.
For which of the following would you expect distribution range to be badly affected if average Global temperature keeps increasing:- a)Stenothermal species
- b)Euryhaline species
- c)Both Stenothermal species and Euryhaline species
- d)Eurythermal species
Correct answer is option 'A'. Can you explain this answer?
For which of the following would you expect distribution range to be badly affected if average Global temperature keeps increasing:
a)
Stenothermal species
b)
Euryhaline species
c)
Both Stenothermal species and Euryhaline species
d)
Eurythermal species
|
Diya Datta answered |
A majority of organisms are restricted to narrow range of temperature. Such organisms are called stenothermal species. The distribution range of these species will be adversely affected if average global temperature keeps increasing.
In a population per capita birth rate is 0.15 and per capita death rate is 0.08 during a unit time period. What is the value of r (intrinsic rate of natural increase) for the given population ?- a)0.023
- b)0.07
- c)0.05
- d)0.25
Correct answer is option 'B'. Can you explain this answer?
In a population per capita birth rate is 0.15 and per capita death rate is 0.08 during a unit time period. What is the value of r (intrinsic rate of natural increase) for the given population ?
a)
0.023
b)
0.07
c)
0.05
d)
0.25
|
Jyoti Sengupta answered |
Intrinsic rate of natural increase (r)
= Birth rate − death rate
=0.15−0.08=0.07
In which of the following interaction/s one species is benefitted while other is harmed?- a)parasitism only
- b)competition only
- c)predation and parasitism
- d)competition and amensalism
Correct answer is option 'C'. Can you explain this answer?
In which of the following interaction/s one species is benefitted while other is harmed?
a)
parasitism only
b)
competition only
c)
predation and parasitism
d)
competition and amensalism
|
Nayanika Dasgupta answered |
In predation and parasitism one species is benefitted while other is harmed. Parasite obtain food from host by harming them.
In a pond, last year there were 30 lotus plants. Through reproduction, 25 new lotus plants were added in one year while 8 plants died. The birth and death rates for the lotus population respectively are ___ and ____ individuals per lotus per year.- a)0.83 , 0.26
- b)0.26, 0.83
- c)0.25 , 0.80
- d)0.80, 0.25
Correct answer is option 'A'. Can you explain this answer?
In a pond, last year there were 30 lotus plants. Through reproduction, 25 new lotus plants were added in one year while 8 plants died. The birth and death rates for the lotus population respectively are ___ and ____ individuals per lotus per year.
a)
0.83 , 0.26
b)
0.26, 0.83
c)
0.25 , 0.80
d)
0.80, 0.25
|
|
Preeti Iyer answered |
Total number of plants (in the beginning ) = 30
New plants added by reproduction = 25
Birth rate (of a population)
New plants added by reproduction = 25
Birth rate (of a population)
=0.83 individuals per lotus per year
Number of plants died =8
“In Competition, the superior competitor eliminates the inferior one”, this statement is called?- a)Gause’s principle
- b)Allen’s rule
- c)Darwinian fitness
- d)All of these
Correct answer is option 'A'. Can you explain this answer?
“In Competition, the superior competitor eliminates the inferior one”, this statement is called?
a)
Gause’s principle
b)
Allen’s rule
c)
Darwinian fitness
d)
All of these
|
Rajesh Datta answered |
E In competition, superior competitor eliminates the inferior one. This statement is called Gause’s competitive exclusion principle. Two closely related competing for same resources cannot co-exist indefinitely and inferior will be eliminated.
In a population unrestricted reproductive capacity is called as[2002]- a)biotic potential
- b)fertility
- c)carrying capacity
- d)birth rate
Correct answer is option 'A'. Can you explain this answer?
In a population unrestricted reproductive capacity is called as
[2002]
a)
biotic potential
b)
fertility
c)
carrying capacity
d)
birth rate
|
Charvi Shah answered |
Carrying capacity refers to the maximum number of individuals that can be sustained by the environment. Birth rate refers to number of births per unit population.
Soil particles determine its[1992]- a)texture
- b)field capacity
- c)water holding capacity
- d)soil flora
Correct answer is option 'A'. Can you explain this answer?
Soil particles determine its
[1992]
a)
texture
b)
field capacity
c)
water holding capacity
d)
soil flora
|
|
Priyanka Iyer answered |
Soil particles size defines its texture. The mineral particles present in soil, vary enosmously in size the fire fiagments. (consisting of sand, silt and clay particles) and coarse fiagments (gravel, copples and stones). The relative proportion's of sand, silt and clay in a soil is referred as soil texture. Fine textured soil have more of clay particles.
Water holding capacity-Larger soil particles like sand, gravel have large pores. This have high less holding capacity and higher percolotion rate field capacity is the of soil moisture or water content held in soil after excess water has drained away.
Water holding capacity-Larger soil particles like sand, gravel have large pores. This have high less holding capacity and higher percolotion rate field capacity is the of soil moisture or water content held in soil after excess water has drained away.
An example of predation is :- a)Cuckoo laying eggs in crow’s nest
- b)Biological control of pest population
- c)Penicilliumwhose toxins kill bacteria
- d)None of the these
Correct answer is option 'B'. Can you explain this answer?
An example of predation is :
a)
Cuckoo laying eggs in crow’s nest
b)
Biological control of pest population
c)
Penicilliumwhose toxins kill bacteria
d)
None of the these
|
Abhishek Choudhary answered |
Biological control method adopted in agricultural pest control are based on the ability of predator to regulate prey population.
Ecology is the study of the relationships between living organisms and:- a)Abiotic and biotic components
- b)Biotic components only
- c)Abiotic components only
- d)Non-living components only
Correct answer is option 'A'. Can you explain this answer?
Ecology is the study of the relationships between living organisms and:
a)
Abiotic and biotic components
b)
Biotic components only
c)
Abiotic components only
d)
Non-living components only
|
Milan Unni answered |
Ecology is the branch of biology that studies the relationships between living organisms and their environment. It is concerned with understanding how organisms interact with both the biotic (living) and abiotic (non-living) components of their surroundings.
The population growth is generally described by the following equation:
What does 'r' represent in the given equation ?- a)Population density at time 't'
- b)Intrinsic rate of natural increase
- c)Carrying capacity
- d)The base of natural logarithm
Correct answer is option 'B'. Can you explain this answer?
The population growth is generally described by the following equation:
What does 'r' represent in the given equation ?
What does 'r' represent in the given equation ?
a)
Population density at time 't'
b)
Intrinsic rate of natural increase
c)
Carrying capacity
d)
The base of natural logarithm
|
|
Riya Banerjee answered |
A population growing in a habitat with limited resources shows initially a lag phase, followed by phases of increase and decrease and finally the population density reaches the carrying capacity. A plot of N in relation to time (t) results in a sigmoid curve. This type of population growth is called Verhulst- Pearl Logistic Growth as explained by the following equation:
Where N = Population density at a time t;
r = Intrinsic rate of natural increase and;
K = Carrying capacity.
r = Intrinsic rate of natural increase and;
K = Carrying capacity.
The plant-animal interactions often involve co-evolution of the mutualists so that- a)the mutually beneficial system could be safeguarded against 'cheaters'
- b)a given plant species can be pollinated only by its partner animal species and no other species
- c)the animal utilises plant not only for ovipositions but also to pollinate the plant
- d)all of these
Correct answer is option 'D'. Can you explain this answer?
The plant-animal interactions often involve co-evolution of the mutualists so that
a)
the mutually beneficial system could be safeguarded against 'cheaters'
b)
a given plant species can be pollinated only by its partner animal species and no other species
c)
the animal utilises plant not only for ovipositions but also to pollinate the plant
d)
all of these
|
Anjali Sharma answered |
Plant-animal interactions involve co-evolution of mutualists. This means, the evolution of the plant (e.g., flower) and the animal (e.g. pollinator species) are closely linked with one another.
Which type of interaction benefits both species involved?- a)Competition
- b)Predation
- c)Mutualism
- d)Parasitism
Correct answer is option 'C'. Can you explain this answer?
Which type of interaction benefits both species involved?
a)
Competition
b)
Predation
c)
Mutualism
d)
Parasitism
|
Hridoy Mehta answered |
Mutualism
Mutualism is a type of interaction between two species in which both species benefit from the relationship. This type of interaction is considered to be mutually beneficial and can occur in a variety of ecosystems and between different types of organisms.
Definition of Mutualism
Mutualism is a form of symbiotic relationship where both species involved benefit from the interaction. It is a cooperative interaction that enhances the survival, growth, and reproduction of both species.
Examples of Mutualism
There are numerous examples of mutualism in nature, demonstrating the wide range of organisms that can engage in this type of interaction. Here are a few examples:
- Pollination: Bees and flowers have a mutualistic relationship. Bees obtain nectar from flowers, which provides them with a food source, while flowers benefit from the transfer of pollen from one flower to another, facilitating reproduction.
- Cleaner Fish and Host Fish: Cleaner fish, such as cleaner wrasses, remove parasites and dead skin from host fish. The cleaner fish benefits by obtaining food, while the host fish benefits from the removal of parasites, improving its health and well-being.
- Leafcutter Ants and Fungus: Leafcutter ants cultivate fungus gardens by cutting and transporting leaves. The ants feed on the fungus, while the fungus benefits from the constant supply of organic matter and protection provided by the ants.
Benefits of Mutualism
Mutualism is advantageous for both species involved due to the following reasons:
- Resource Sharing: Both species share resources, such as food, shelter, or protection, which increases their chances of survival and reproduction.
- Increased Fitness: By working together, both species can increase their overall fitness and reproductive success. This can lead to population growth and long-term survival.
- Enhanced Nutrient Cycling: Mutualistic relationships can improve nutrient cycling in ecosystems, benefiting the overall health and productivity of the environment.
Conclusion
Mutualism is a type of interaction that benefits both species involved. It is a cooperative relationship that enhances survival, growth, and reproduction. Examples of mutualism can be found in various ecosystems, demonstrating the importance of this type of interaction in nature.
Read the following text and answer the following question on the basis of the same:
Growth of a population with time shows specific and predictable patterns. Two types of growth pattern of population are exponential and logistic growth. When resources in the habitat are unlimited each species has the ability to realize fully its innate potential to grow in number. Then the population grows in exponential fashion. When the resources are limited the growth curve shows an initial slow rate and then it accelerates and finally slows giving the growth curve which is sigmoid.
Q. Identify the correct equation that represents the exponential population growth curve:
- a)dN/dt = IN
- b)Both (A) and (C)
- c)Nt =N0ert
- d)dN/dt = rN
Correct answer is option 'D'. Can you explain this answer?
Read the following text and answer the following question on the basis of the same:
Growth of a population with time shows specific and predictable patterns. Two types of growth pattern of population are exponential and logistic growth. When resources in the habitat are unlimited each species has the ability to realize fully its innate potential to grow in number. Then the population grows in exponential fashion. When the resources are limited the growth curve shows an initial slow rate and then it accelerates and finally slows giving the growth curve which is sigmoid.
Q. Identify the correct equation that represents the exponential population growth curve:
a)
dN/dt = IN
b)
Both (A) and (C)
c)
Nt =N0ert
d)
dN/dt = rN
|
Dev Patel answered |
At the constant birth rate in population through time and is never limited by food or disease, known as exponential growth.
The formula of exponential growth is dN/dt=rN where dN/dt is the rate of change in population size, r is the biotic potential and N is the population size.
The formula of exponential growth is dN/dt=rN where dN/dt is the rate of change in population size, r is the biotic potential and N is the population size.
Which of the following algae are found in deepest ocean waters?- a)Red algae
- b)Yellow algae
- c)Green algae
- d)Brown algae
Correct answer is option 'A'. Can you explain this answer?
Which of the following algae are found in deepest ocean waters?
a)
Red algae
b)
Yellow algae
c)
Green algae
d)
Brown algae
|
|
Pranitha Varma answered |
Red algae are found in deepest ocean waters
because it contains phycoerithrin pigment it can absorbs blue light which penetrates the most deep water for photosynthesis and appears Red because it reflects red light
so Red algae are found in deepest ocean waters
because it contains phycoerithrin pigment it can absorbs blue light which penetrates the most deep water for photosynthesis and appears Red because it reflects red light
so Red algae are found in deepest ocean waters
Association of animals when both partners are benefitted[1993]- a)colony
- b)mutualism
- c)commensalism
- d)amensalism
Correct answer is option 'B'. Can you explain this answer?
Association of animals when both partners are benefitted
[1993]
a)
colony
b)
mutualism
c)
commensalism
d)
amensalism
|
Shanaya Rane answered |
Mutualism type of interactions are shown in plant roots in mycorrhizal region.
Choose the correct sequence of stages of growth curve for bacteria[2002]- a)Lag, log, stationary, decline phase
- b)Lag, log, stationary phase
- c)Stationary, lag, log, decline phase
- d)Decline, lag, log phase
Correct answer is option 'A'. Can you explain this answer?
Choose the correct sequence of stages of growth curve for bacteria
[2002]
a)
Lag, log, stationary, decline phase
b)
Lag, log, stationary phase
c)
Stationary, lag, log, decline phase
d)
Decline, lag, log phase
|
Dipika Das answered |
The growth curve for bacteria is sigmoid. First phase is the phase of slow growth- Lag phase. Second phase is the period of accelerated growth - Log phase. Third phase is the phase when growth rate becomes stable - Stationary phase. Finally growth rate declines.
Asymptote in a logistic growth curve is obtained when [2017]- a)K = N
- b)K > N
- c)K < N
- d)the value of 'r' approaches zero.
Correct answer is option 'A'. Can you explain this answer?
Asymptote in a logistic growth curve is obtained when [2017]
a)
K = N
b)
K > N
c)
K < N
d)
the value of 'r' approaches zero.
|
|
Raghav Bansal answered |
Asymptote in a logistic growth curve is obtained when population density (N) reaches the carrying capacity (K), i.e., N = K.
Which type of interaction does a mycorrhiza show?- a)Predation
- b)Parasitism
- c)Commensalism
- d)Mutualism
Correct answer is option 'D'. Can you explain this answer?
Which type of interaction does a mycorrhiza show?
a)
Predation
b)
Parasitism
c)
Commensalism
d)
Mutualism
|
Ambition Institute answered |
Mycorrhiza is a mutualistic interaction between fungi and plants. About 80-90 percent of plants rely on mycorrhiza for the uptake of minerals (nitrogen, phosphorous, etc.) from the soil. While plants supply essential nutrients such as sugars to fungi for their proper growth.
An age pyramid with a wide base and narrow top indicates a population that is:- a)Changing
- b)Stable
- c)Declining
- d)Growing rapidly
Correct answer is option 'D'. Can you explain this answer?
An age pyramid with a wide base and narrow top indicates a population that is:
a)
Changing
b)
Stable
c)
Declining
d)
Growing rapidly
|
|
Rajesh Gupta answered |
An age pyramid with a wide base and narrow top indicates a population that is growing rapidly.
In an age pyramid, the width of each age group represents the proportion or percentage of individuals in that specific age group. A wide base indicates a larger population of young individuals, while a narrow top indicates a smaller population of older individuals.
When the base of an age pyramid is wide and the subsequent age groups gradually decrease in width towards the top, it suggests that there is a higher proportion of young individuals compared to older individuals. This is indicative of a population that is growing rapidly because there is a high birth rate.
The formula for exponential population growth is- a)dN/rN = dt
- b)r N/dN = dt
- c)dt/dN = r N
- d)dN/dt = r N
Correct answer is option 'D'. Can you explain this answer?
The formula for exponential population growth is
a)
dN/rN = dt
b)
r N/dN = dt
c)
dt/dN = r N
d)
dN/dt = r N
|
Abhiram Nair answered |
Ans.
Formula = the rate of change in population size) = (the contribution of each individual to population growth) x (the number of individuals in the population
Exponential growth is observed in a population when- a)resources in the habitat are unlimited
- b)each species has the ability to realise its full innate potential
- c)both (a) and (b)
- d)none of these
Correct answer is option 'C'. Can you explain this answer?
Exponential growth is observed in a population when
a)
resources in the habitat are unlimited
b)
each species has the ability to realise its full innate potential
c)
both (a) and (b)
d)
none of these
|
|
Raghav Bansal answered |
When food and space for a population are unlimited, each species has the ability to realise fully its inherited potential to grow. Then the population grows in an exponential or geometric ratio.
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