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Ecosystem follows:- a)only first law of thermodynamics
- b)only second law of thermodynamics
- c)both first and second laws of thermodynamics
- d)only third law of thermodynamics
Correct answer is option 'C'. Can you explain this answer?
Ecosystem follows:
a)
only first law of thermodynamics
b)
only second law of thermodynamics
c)
both first and second laws of thermodynamics
d)
only third law of thermodynamics
|
Vijay Bansal answered |
The first law, also known as Law of Conservation of Energy, states that energy cannot be created or destroyed in an isolated system. The third law of thermodynamics states that the entropy of a system approaches a constant value as the temperature approaches absolute zero.
The common nitrogen-fixer in paddy fields is- a)Rhizobium
- b)Azospirillum
- c)Frankia
- d)Oscillatoria
Correct answer is 'B'. Can you explain this answer?
The common nitrogen-fixer in paddy fields is
a)
Rhizobium
b)
Azospirillum
c)
Frankia
d)
Oscillatoria
|
Nandini Patel answered |
Azospirillum is a nitrogen fixing bacterium in paddy fields. It is very useful soil and root bacterium. It is an associative symbiotic N2-fixing bacteria. When it is added to the soil, it multiplies in millions and can supply 20-40 Kg of nitrogen per hectare, per season. It also produces growth promoting substances like Indole Acetic Acid (IAA), gibberellins and promotes root proliferation. These substances improve the plant growth and yield.
Secondary productivity is the rate of formation of new organic matter by- a)Decomposer
- b)Consumer
- c)Producer
- d)Parasite
Correct answer is option 'B'. Can you explain this answer?
Secondary productivity is the rate of formation of new organic matter by
a)
Decomposer
b)
Consumer
c)
Producer
d)
Parasite
|
Rhea Sharma answered |
Explanation:
Secondary productivity is the rate of formation of new organic matter by the consumers in an ecosystem. It is the amount of biomass produced by the heterotrophic organisms from the organic matter they consume. In other words, it is the rate at which the consumers convert the organic matter they eat into new biomass.
Factors affecting secondary productivity:
The secondary productivity of an ecosystem depends on various factors such as:
1. Availability of food: The availability of food resources affects the secondary productivity of consumers. If the food is scarce, the consumers will have less energy to convert into biomass, resulting in lower productivity.
2. Nutrient availability: The availability of nutrients such as nitrogen and phosphorus affects the growth and reproduction of consumers, which in turn affects their productivity.
3. Temperature: Temperature affects the metabolic rate of the consumers, which in turn affects their productivity. Higher temperatures generally result in higher productivity.
4. Predation: The presence of predators affects the behavior of the consumers, which in turn affects their productivity.
5. Competition: The presence of competing species affects the availability of food resources, which in turn affects the productivity of the consumers.
Importance of secondary productivity:
Secondary productivity is an important measure of the energy flow in an ecosystem. It provides information about the efficiency of energy transfer from the producers to the consumers. It also helps in understanding the food web dynamics and the role of consumers in maintaining the balance of the ecosystem.
Conclusion:
In conclusion, secondary productivity is the rate of formation of new organic matter by the consumers in an ecosystem. It is influenced by various factors such as food availability, nutrient availability, temperature, predation, and competition. It is an important measure of energy flow in an ecosystem and provides insights into the food web dynamics and the role of consumers in maintaining the balance of the ecosystem.
Secondary productivity is the rate of formation of new organic matter by the consumers in an ecosystem. It is the amount of biomass produced by the heterotrophic organisms from the organic matter they consume. In other words, it is the rate at which the consumers convert the organic matter they eat into new biomass.
Factors affecting secondary productivity:
The secondary productivity of an ecosystem depends on various factors such as:
1. Availability of food: The availability of food resources affects the secondary productivity of consumers. If the food is scarce, the consumers will have less energy to convert into biomass, resulting in lower productivity.
2. Nutrient availability: The availability of nutrients such as nitrogen and phosphorus affects the growth and reproduction of consumers, which in turn affects their productivity.
3. Temperature: Temperature affects the metabolic rate of the consumers, which in turn affects their productivity. Higher temperatures generally result in higher productivity.
4. Predation: The presence of predators affects the behavior of the consumers, which in turn affects their productivity.
5. Competition: The presence of competing species affects the availability of food resources, which in turn affects the productivity of the consumers.
Importance of secondary productivity:
Secondary productivity is an important measure of the energy flow in an ecosystem. It provides information about the efficiency of energy transfer from the producers to the consumers. It also helps in understanding the food web dynamics and the role of consumers in maintaining the balance of the ecosystem.
Conclusion:
In conclusion, secondary productivity is the rate of formation of new organic matter by the consumers in an ecosystem. It is influenced by various factors such as food availability, nutrient availability, temperature, predation, and competition. It is an important measure of energy flow in an ecosystem and provides insights into the food web dynamics and the role of consumers in maintaining the balance of the ecosystem.
Acclimatisation is- a)Pure-line selection
- b)Introduction
- c)Pure-line breeding
- d)Adaptation to new environment
Correct answer is option 'D'. Can you explain this answer?
Acclimatisation is
a)
Pure-line selection
b)
Introduction
c)
Pure-line breeding
d)
Adaptation to new environment
|
Rajeev Saxena answered |
Acclimatization or acclimatisation (also called acclimation or acclimatation) is the process in which an individual organism adjusts to a change in its environment (such as a change in altitude, temperature, humidity, photoperiod, or pH), allowing it to maintain performance across a range of environmental conditions.
. Which one of the following is considered as a pioneer community in xerarch?- a)Forest stage
- b)Perennial herb
- c)Annual herb
- d)Lichen
Correct answer is option 'D'. Can you explain this answer?
. Which one of the following is considered as a pioneer community in xerarch?
a)
Forest stage
b)
Perennial herb
c)
Annual herb
d)
Lichen
|
Gayatri Pillai answered |
Xerarch succession is a type of ecological succession that occurs on bare rock or soil that has no life. In xerarch succession, pioneer communities colonize the area and gradually change the environment, making it more suitable for other organisms to inhabit.
Among the options given, lichen is considered as a pioneer community in xerarch succession. Here are the reasons why:
What are lichens?
- Lichens are composite organisms that arise from algae or cyanobacteria living among filaments of multiple fungi in a symbiotic relationship.
- They can grow on rocks, soil, and bark of trees, where no other organisms can survive.
How do lichens initiate xerarch succession?
- Lichens secrete acids that dissolve the rock surface and release minerals, which contribute to the formation of soil.
- As lichens die and decompose, they add organic matter to the soil, further enhancing its fertility.
- Lichens also trap moisture and nutrients from the air, which helps to create a more hospitable environment for other organisms.
What happens after lichens?
- As lichens continue to grow and die, they create a thin layer of soil that can support the growth of other organisms, such as mosses and ferns.
- These plants further modify the environment, creating more soil, retaining moisture, and providing habitats for insects and other animals.
- Over time, the community of organisms becomes more complex and diverse, eventually leading to the establishment of a forest or other mature ecosystem.
Therefore, lichens are considered as a pioneer community in xerarch succession, as they are the first organisms to colonize the area and initiate the process of ecological succession.
Among the options given, lichen is considered as a pioneer community in xerarch succession. Here are the reasons why:
What are lichens?
- Lichens are composite organisms that arise from algae or cyanobacteria living among filaments of multiple fungi in a symbiotic relationship.
- They can grow on rocks, soil, and bark of trees, where no other organisms can survive.
How do lichens initiate xerarch succession?
- Lichens secrete acids that dissolve the rock surface and release minerals, which contribute to the formation of soil.
- As lichens die and decompose, they add organic matter to the soil, further enhancing its fertility.
- Lichens also trap moisture and nutrients from the air, which helps to create a more hospitable environment for other organisms.
What happens after lichens?
- As lichens continue to grow and die, they create a thin layer of soil that can support the growth of other organisms, such as mosses and ferns.
- These plants further modify the environment, creating more soil, retaining moisture, and providing habitats for insects and other animals.
- Over time, the community of organisms becomes more complex and diverse, eventually leading to the establishment of a forest or other mature ecosystem.
Therefore, lichens are considered as a pioneer community in xerarch succession, as they are the first organisms to colonize the area and initiate the process of ecological succession.
Correct sequence for decomposition process is:
- a)fragmentation -> leaching -> catabolism -> mineralisation
- b)fragmentation -> leaching -> mineralisation -> humification
- c)leaching -> fragmentation -> humification -> mineralisation
- d)fragmentation -> catabolism -> leaching -> mineralisation
Correct answer is option 'D'. Can you explain this answer?
Correct sequence for decomposition process is:
a)
fragmentation -> leaching -> catabolism -> mineralisation
b)
fragmentation -> leaching -> mineralisation -> humification
c)
leaching -> fragmentation -> humification -> mineralisation
d)
fragmentation -> catabolism -> leaching -> mineralisation
|
Gaurav Kumar answered |
Decomposition is the process that involves the breakdown of complex organic matter or biomass from the body of dead plants and animals with the help of decomposers into inorganic raw materials such as carbon dioxide, water, and other nutrients.
The various processes involved in decomposition are as follows:
➢ Fragmentation
➢ Fragmentation
- It is the first step in the process of decomposition.
- It involves the breakdown of detritus into smaller pieces by the action of detritivores such as earthworms.
➢ Leaching
- It is a process where the water soluble nutrients go down into the soil layers and get locked as unavailable salts.
➢ Catabolism
- It is a process in which bacteria and fungi degrade detritus through various enzymes into smaller pieces.
➢ Humification
- The next step is humification which leads to the formation of a dark-coloured colloidal substance called humus, which acts as reservoir of nutrients for plants.
➢ Mineralization
- The humus is further degraded by the action of microbes, which finally leads to the release of inorganic nutrients into the soil.
- This process of releasing inorganic nutrients from the humus is known as mineralization.
The final stable community in ecological succession is- a)Sere
- b)Climax
- c)Pioneers
- d)Carnivores
Correct answer is option 'B'. Can you explain this answer?
The final stable community in ecological succession is
a)
Sere
b)
Climax
c)
Pioneers
d)
Carnivores
|
Pooja Mehta answered |
The community begins with relatively few pioneering plants and animals and develops through increasing complexity until it becomes stable or self-perpetuating as a climax community. The "engine" of succession, the cause of ecosystem change, is the impact of establishedspecies upon their own environments.
Which one of the following statements is CORRECT for secondary succession?
- a)It begins on a bare rock.
- b)It occurs on a deforested site.
- c)It follows primary succession.
- d)It is similar to primary succession except that it has a relatively fast pace.
Correct answer is option 'B'. Can you explain this answer?
Which one of the following statements is CORRECT for secondary succession?
a)
It begins on a bare rock.
b)
It occurs on a deforested site.
c)
It follows primary succession.
d)
It is similar to primary succession except that it has a relatively fast pace.
|
|
Rohit Shah answered |
-
Option A: It begins on a bare rock. This is incorrect as it describes primary succession, not secondary.Option B: It occurs on a deforested site. This is correct. Secondary succession occurs in areas where a community has been removed; it is the series of community changes which take place on a previously colonized, but disturbed or damaged habitat.Option C: It follows primary succession. While secondary succession does come after primary succession, this statement on its own is not fully descriptive of secondary succession.Option D: It is similar to primary succession except that it has a relatively fast pace. This is also correct; however, it is less specific than Option B. Secondary succession is typically faster than primary succession because the soil already exists, and often some remnants of the previous community remain.The most accurate and specific statement for secondary succession is:Option B: It occurs on a deforested site.
Ecosystem is- a)Open
- b)Both open and close
- c)Close
- d)Neither opened nor closed
Correct answer is option 'A'. Can you explain this answer?
Ecosystem is
a)
Open
b)
Both open and close
c)
Close
d)
Neither opened nor closed
|
|
Rajat Kapoor answered |
An ecosystem includes all of the living things (plants, animals and organisms) in a given area, interacting with each other, and also with their non-living environments (weather, earth, sun, soil, climate, atmosphere). Ecosystems are the foundations of the Biosphere and they determine the health of the entire earth system.
Humus will never be:
- a)Good for plant growth.
- b)Resistant to microbial action.
- c)Reservoir of nutrients.
- d)all of these
- e)None of these.
Correct answer is option 'E'. Can you explain this answer?
Humus will never be:
a)
Good for plant growth.
b)
Resistant to microbial action.
c)
Reservoir of nutrients.
d)
all of these
e)
None of these.
|
|
Rohan Singh answered |
- Humus is a dark brown amorphous gummy substance formed by partial decomposition of plant and animal matter.
- It is not good for plant growth.
- Humus is quite resistant to microbial action.
- It is a reservoir of nutrients and is helpful in the maintenance of soil moisture as well as aeration.
Hence, None of these statements is correct about Humus.
Which of the following is correct?a)GPP + NPP = Rb)NPP – R = GPPc)GPP – R = NPPd)NPP – GPP = RCorrect answer is option 'C'. Can you explain this answer?
|
Srishti Sen answered |
Net primary productivity (NPP) is equal to Gross primary productivity (GPP) minus Respiration loss (R). NPP is the available biomass for the consumption of heterotrophs in the ecosystem.
Which one of the following is a denitrifying bacterium?- a)Pseudomonas
- b)Escherichia coli
- c)Nitrobacter
- d)Nitrosomonas
Correct answer is option 'A'. Can you explain this answer?
Which one of the following is a denitrifying bacterium?
a)
Pseudomonas
b)
Escherichia coli
c)
Nitrobacter
d)
Nitrosomonas
|
Anjali Iyer answered |
Denitrifying bacteria, microorganisms whose action results in the conversion of nitrates in soil to free atmospheric nitrogen, thus depleting soil fertility and reducing agricultural productivity. Thiobacillus denitrificans, Micrococcus denitrificans, and some species of Serratia, Pseudomonas, and Achromobacter are implicated as denitrifiers. Pseudomonas aeruginosa can, under anaerobic conditions (as in swampy or water-logged soils), reduce the amount of fixed nitrogen (as fertilizer) by up to 50 percent. Without denitrification, however, the Earth’s supply of nitrogen would eventually accumulate in the oceans, since nitrates are highly soluble and are continuously leached from the soil into nearby bodies of water. See also nitrogen cycle.
Exponential growth occurs in the population in which sufficient
- a)Water is abundant.
- b)Sufficient area is available.
- c)All of the these.
- d)Food and other nutrient are available.
Correct answer is option 'C'. Can you explain this answer?
Exponential growth occurs in the population in which sufficient
a)
Water is abundant.
b)
Sufficient area is available.
c)
All of the these.
d)
Food and other nutrient are available.
|
Krish Saha answered |
Exponential growth occurs in the population in which sufficient food and nutrients are available in sufficient amount. The rate of growth is very fast in this kinds of growth.
Exponential growth in a population occurs when:
- Food and nutrients are plentiful.
- Water is abundant.
- There is sufficient living space.
These conditions ensure that individuals can reproduce rapidly without facing resource limitations, leading to a fast and continuous increase in population size. Thus, the correct answer is C: All of these.
A natural reservoir of phosphorus is- a)Fossils
- b)Rock
- c)Sea water
- d)Animal bones
Correct answer is option 'B'. Can you explain this answer?
A natural reservoir of phosphorus is
a)
Fossils
b)
Rock
c)
Sea water
d)
Animal bones
|
|
Anjali Iyer answered |
The natural reservoir of phosphate is rock which contains phosphorus in the form of phosphates when rocks are weathered, minute amounts of these phosphate dissolve in soil solution and are absorbed by the roots of the plants. Herbivores and other animals obtain this element from plants.
Which one of the following is the most important service provided by ecosystems?- a)soil formation
- b)aesthetic values
- c)pollination
- d)water purification
Correct answer is option 'A'. Can you explain this answer?
Which one of the following is the most important service provided by ecosystems?
a)
soil formation
b)
aesthetic values
c)
pollination
d)
water purification
|
Mehul Iyer answered |
Ecosystem services includes all activities performed by nature to benefits of human beings. The most important ecological service includes soil formation. Soil is essential for growth of plants that provide food to all living forms.
A detritus food chain will start with which of the following?- a)Protozoans
- b)Rhizophora species
- c)Bacteria & fungi
- d)Earthworm
Correct answer is option 'C'. Can you explain this answer?
A detritus food chain will start with which of the following?
a)
Protozoans
b)
Rhizophora species
c)
Bacteria & fungi
d)
Earthworm
|
Rajesh Datta answered |
A detritus food chain begins with dead organic matter. It is made of decomposers which are heterotrophic organism fungi and bacteria.Rhizophora species is a saprophyticheterotrophs.
Available organic matter for herbivores is represented by:- a)Secondary productivity
- b)GPP
- c)NPP
- d)All the these
Correct answer is option 'C'. Can you explain this answer?
Available organic matter for herbivores is represented by:
a)
Secondary productivity
b)
GPP
c)
NPP
d)
All the these
|
Charvi Shah answered |
The organic matter available for herbivores is called net primary productivity (NPP). Total amount of organic matter fix during photosynthesis is called Gross primary productivity (GPP).
There are only 4 or 5 trophic levels in food chain of an ecosystem due to :- a)Limited number of members in biotic community
- b)Loss of energy at successive levels
- c)Carrying capacity
- d)Environmental resistance
Correct answer is option 'B'. Can you explain this answer?
There are only 4 or 5 trophic levels in food chain of an ecosystem due to :
a)
Limited number of members in biotic community
b)
Loss of energy at successive levels
c)
Carrying capacity
d)
Environmental resistance
|
|
Krish Saha answered |
In most of the food chain of ecosystem only 4 to 5 trophic levels are present because loss of energy at successive levels is very high. Only 10% of energy is transferred to next trophic level.
Which one of the following is not used for construction of ecological pyramids?- a)Dry weight
- b)Number of individuals
- c) Fresh weight
- d)Rate of energy flow
Correct answer is option 'C'. Can you explain this answer?
Which one of the following is not used for construction of ecological pyramids?
a)
Dry weight
b)
Number of individuals
c)
Fresh weight
d)
Rate of energy flow
|
Sanvi Patel answered |
Option c) Fresh weight is correct because
An ecological pyramid is a graphical representation of the relationship between different organisms. It shows the biomass at each trophic level of an ecosystem. It is of three types, pyramid of numbers, the pyramid of energy and the pyramid of biomass. The pyramid of numbers indicates the total number of individuals at each trophic level. The pyramid of energy indicates the rate of energy flow. Pyramid of biomass indicates the dry weight of living organisms at each trophic level.
Which of the following is not an ecological parameter?- a)Stratification
- b)Number
- c)Energy
- d)Biomass
Correct answer is option 'A'. Can you explain this answer?
Which of the following is not an ecological parameter?
a)
Stratification
b)
Number
c)
Energy
d)
Biomass
|
Mahesh Saini answered |
Ecological parameter includes, biomass, energy and number of individual in the ecosystem. Stratification is not a part of ecological parameter.
Organism/s living as both producer as well as consumer is/are:- a)Algae & fungi
- b)Nepenthes & Drocera
- c)Cuscuta
- d)Phytoplankton
Correct answer is option 'B'. Can you explain this answer?
Organism/s living as both producer as well as consumer is/are:
a)
Algae & fungi
b)
Nepenthes & Drocera
c)
Cuscuta
d)
Phytoplankton
|
Arpita Tiwari answered |
Nepenthes (pitcher plant) and Drocera are insectivores plants to compensate theirprotein requirement. They have green leaves that perform photosynthesis process. So, they act as both producer as well as consumer.
Which of the following ecological pyramid is always erect and upright?- a)pyramid of biomass
- b)pyramid of energy
- c)pyramid of number
- d)none of these
Correct answer is option 'B'. Can you explain this answer?
Which of the following ecological pyramid is always erect and upright?
a)
pyramid of biomass
b)
pyramid of energy
c)
pyramid of number
d)
none of these
|
Ishani Nambiar answered |
Pyramid of energy is always erect and upright because the amount of energy get reduce at each trophic level from prouder to consumers.
The decomposition of organic matter is brought about by- a)Protozoans
- b)Plants
- c)Microorganisms
- d)None of the above
Correct answer is option 'C'. Can you explain this answer?
The decomposition of organic matter is brought about by
a)
Protozoans
b)
Plants
c)
Microorganisms
d)
None of the above
|
Shruti Bora answered |
Microorganisms like bacteria etc decompose organic matter.
Phosphorus will not make part of:- a)nucleic acids
- b)ATP
- c)teeth
- d)amino acids
Correct answer is option 'D'. Can you explain this answer?
Phosphorus will not make part of:
a)
nucleic acids
b)
ATP
c)
teeth
d)
amino acids
|
Subham Chavan answered |
Phosphorus is not present in amino acids. Nucleic acids, ATP and Teeth contain phosphorus. Amino acids polymerases to form protein.
In which of the following places, succession will occur in short time?- a)on a bare rock
- b)in heavily overgrazed pasture
- c)in a small oligotrophic lake
- d)area exposed by a retreating glacier
Correct answer is option 'B'. Can you explain this answer?
In which of the following places, succession will occur in short time?
a)
on a bare rock
b)
in heavily overgrazed pasture
c)
in a small oligotrophic lake
d)
area exposed by a retreating glacier
|
Abhishek Choudhary answered |
Succession will occur in short time in heavily overgrazed pasture. If organic compound are already available in the place new organisms will develops faster as compare to bare land without organic matter.
Term ecosystem was introduced by :- a)Charles Elton
- b)Haeckel
- c)Lindemann
- d)Tansley
Correct answer is option 'D'. Can you explain this answer?
Term ecosystem was introduced by :
a)
Charles Elton
b)
Haeckel
c)
Lindemann
d)
Tansley
|
Shounak Nair answered |
Term ecosystem was introduced by Tansley. Ecosystem is the functionalunit of nature where living and non-living components interact with each other.
In an ecosystem, the cycling of nutrients is known as- a)Biogeochemical cycle
- b)Geological cycle
- c)Chemical cycle
- d)Geochemical cycle
Correct answer is option 'A'. Can you explain this answer?
In an ecosystem, the cycling of nutrients is known as
a)
Biogeochemical cycle
b)
Geological cycle
c)
Chemical cycle
d)
Geochemical cycle
|
Aditi Rai answered |
Cycling of nutrients. from bio..mean living thing. to geo ....mean soil. chemical.......in the form of chemicals. all 3 are included...so option A is corrrect
Which one of the following is a sedimentary cycle?- a)Oxygen cycle
- b)Phosphorus cycle
- c)Hydrogen cycle
- d)Carbon cycle
Correct answer is option 'B'. Can you explain this answer?
Which one of the following is a sedimentary cycle?
a)
Oxygen cycle
b)
Phosphorus cycle
c)
Hydrogen cycle
d)
Carbon cycle
|
|
Ankit Iyer answered |
Phosphorus cycle is a sedimentary cycle.
Explanation:
The phosphorus cycle is a sedimentary cycle that involves the movement of phosphorus from the earth's crust to living organisms and back to the earth's crust. Here are some key points about the phosphorus cycle:
1. Phosphorus is an essential nutrient for all living organisms, as it is a component of DNA, RNA, and ATP.
2. Phosphorus is found in rocks and minerals in the earth's crust, and it is released into the environment through weathering and erosion.
3. Once released into the environment, phosphorus can be taken up by plants and incorporated into their tissues.
4. Animals that eat these plants then acquire phosphorus, and the nutrient is passed up the food chain.
5. When plants and animals die, their tissues decompose and release phosphorus back into the soil.
6. Over time, phosphorus can become trapped in sediments at the bottom of bodies of water, where it can eventually become part of the earth's crust once again.
7. Human activities, such as the use of fertilizers, can increase the amount of phosphorus in the environment, which can lead to problems such as algal blooms in bodies of water.
In summary, the phosphorus cycle is a sedimentary cycle that involves the movement of phosphorus from the earth's crust to living organisms and back to the earth's crust.
Explanation:
The phosphorus cycle is a sedimentary cycle that involves the movement of phosphorus from the earth's crust to living organisms and back to the earth's crust. Here are some key points about the phosphorus cycle:
1. Phosphorus is an essential nutrient for all living organisms, as it is a component of DNA, RNA, and ATP.
2. Phosphorus is found in rocks and minerals in the earth's crust, and it is released into the environment through weathering and erosion.
3. Once released into the environment, phosphorus can be taken up by plants and incorporated into their tissues.
4. Animals that eat these plants then acquire phosphorus, and the nutrient is passed up the food chain.
5. When plants and animals die, their tissues decompose and release phosphorus back into the soil.
6. Over time, phosphorus can become trapped in sediments at the bottom of bodies of water, where it can eventually become part of the earth's crust once again.
7. Human activities, such as the use of fertilizers, can increase the amount of phosphorus in the environment, which can lead to problems such as algal blooms in bodies of water.
In summary, the phosphorus cycle is a sedimentary cycle that involves the movement of phosphorus from the earth's crust to living organisms and back to the earth's crust.
An ecological succession on bare land proceeds towards:- a)Increasing dryness
- b)Increasing wetness
- c)Decreasing wetness
- d)None of these
Correct answer is option 'B'. Can you explain this answer?
An ecological succession on bare land proceeds towards:
a)
Increasing dryness
b)
Increasing wetness
c)
Decreasing wetness
d)
None of these
|
|
Ishani Nambiar answered |
An ecological succession on bare land proceeds towards increasing wetness. Availability of water help in faster growth of organism including plants.
Germplasm conservation at liquid N2 temperature is- a)Stratification
- b)Cryopreservation
- c)Scarification
- d)None of the above
Correct answer is option 'B'. Can you explain this answer?
Germplasm conservation at liquid N2 temperature is
a)
Stratification
b)
Cryopreservation
c)
Scarification
d)
None of the above
|
Nupur Juyal answered |
Cryopreservation is storing cells,tissues etc. in liq. nitrogen at -196 degree celsius. extensively used in germplasm collection.
Flow of energy in our ecosystem takes place :- a)only in one direction
- b)possible in two directions
- c)in three dimensions
- d)may occur in multiple directions
Correct answer is option 'A'. Can you explain this answer?
Flow of energy in our ecosystem takes place :
a)
only in one direction
b)
possible in two directions
c)
in three dimensions
d)
may occur in multiple directions
|
Aniket Chawla answered |
In ecosystem, flow of energy takes place in only one direction. The flow of energy takes place from producers to final consumers. Energy present in one trophic levels neversreturn back to producer.
Conditions favouring decomposition are :- a)high temperature and intermediate humidity
- b)low temperature and low humidity
- c)low temperature and high humidity
- d)high temperature and low humidity
Correct answer is option 'A'. Can you explain this answer?
Conditions favouring decomposition are :
a)
high temperature and intermediate humidity
b)
low temperature and low humidity
c)
low temperature and high humidity
d)
high temperature and low humidity
|
|
Tarun Saha answered |
**Explanation:**
Decomposition is the process by which organic matter breaks down into simpler substances, such as carbon dioxide, water, and minerals. It is a natural process that is essential for nutrient recycling in ecosystems.
Conditions that favor decomposition are important to understand because they can determine the rate at which organic matter decomposes and the types of organisms involved in the process.
The correct answer to the given question is option 'A', which states that high temperature and intermediate humidity favor decomposition. Let's understand why this is the case:
**1. High Temperature:**
- Decomposition is an enzymatic process, meaning it is facilitated by the action of enzymes produced by microorganisms, such as bacteria and fungi.
- Enzymatic reactions are generally more efficient at higher temperatures because they increase the rate of biochemical reactions.
- High temperatures accelerate the metabolic activity of decomposer organisms, leading to faster decomposition rates.
**2. Intermediate Humidity:**
- Decomposer organisms require a certain level of moisture to carry out their metabolic processes effectively.
- If the humidity is too high, the excessive moisture can create an anaerobic environment (lack of oxygen) that is unfavorable for many decomposer organisms.
- If the humidity is too low, the lack of moisture restricts the activity of decomposer organisms.
- Intermediate humidity provides the ideal conditions for decomposer organisms to thrive and efficiently decompose organic matter.
**Conclusion:**
In conclusion, the correct answer to the given question is option 'A' (high temperature and intermediate humidity) because these conditions provide the ideal environment for the activity of decomposer organisms, leading to faster and more efficient decomposition of organic matter.
Decomposition is the process by which organic matter breaks down into simpler substances, such as carbon dioxide, water, and minerals. It is a natural process that is essential for nutrient recycling in ecosystems.
Conditions that favor decomposition are important to understand because they can determine the rate at which organic matter decomposes and the types of organisms involved in the process.
The correct answer to the given question is option 'A', which states that high temperature and intermediate humidity favor decomposition. Let's understand why this is the case:
**1. High Temperature:**
- Decomposition is an enzymatic process, meaning it is facilitated by the action of enzymes produced by microorganisms, such as bacteria and fungi.
- Enzymatic reactions are generally more efficient at higher temperatures because they increase the rate of biochemical reactions.
- High temperatures accelerate the metabolic activity of decomposer organisms, leading to faster decomposition rates.
**2. Intermediate Humidity:**
- Decomposer organisms require a certain level of moisture to carry out their metabolic processes effectively.
- If the humidity is too high, the excessive moisture can create an anaerobic environment (lack of oxygen) that is unfavorable for many decomposer organisms.
- If the humidity is too low, the lack of moisture restricts the activity of decomposer organisms.
- Intermediate humidity provides the ideal conditions for decomposer organisms to thrive and efficiently decompose organic matter.
**Conclusion:**
In conclusion, the correct answer to the given question is option 'A' (high temperature and intermediate humidity) because these conditions provide the ideal environment for the activity of decomposer organisms, leading to faster and more efficient decomposition of organic matter.
Detritivores break down the detritus by the process called- a)Mineralisation
- b)Humification
- c)Leaching
- d)Fragmentation
Correct answer is option 'D'. Can you explain this answer?
Detritivores break down the detritus by the process called
a)
Mineralisation
b)
Humification
c)
Leaching
d)
Fragmentation
|
|
Rajeev Saxena answered |
Fragmentation or clonal fragmentation in multicellular or colonial organisms is a form of asexual reproduction or cloning in which an organism is split into fragments. Each of these fragments develop into matured, fully grown individuals that are clones of the original organism.
The splitting may or may not be intentional – it may or may not occur due to man-made or natural damage by the environment or predators. This kind of organism may develop specific organs or zones that may be shed or easily broken off. If the splitting occurs without the prior preparation of the organism, both fragments must be able to regenerate the complete organism for it to function as reproduction.
Fragmentation, also known as splitting, as a method of reproduction is seen in many organisms such as filamentous cyanobacteria, molds, lichens, many plants, and animals such as sponges, acoel flatworms, some annelid worms and sea stars.
Forest controls drought through- a)Functioning as water shed.
- b)Lot of water plant
- c)Retention of water and prevention of soil erosion.
- d) Increasing rainfall
Correct answer is option 'D'. Can you explain this answer?
Forest controls drought through
a)
Functioning as water shed.
b)
Lot of water plant
c)
Retention of water and prevention of soil erosion.
d)
Increasing rainfall
|
|
Akshat Joshi answered |
The correct answer is option 'D' i.e., retention of water and prevention of soil erosion.
Explanation:
Forests are essential for the survival of life on earth. They are responsible for various ecological, environmental, and social benefits. Forests play a crucial role in controlling drought by retaining water and preventing soil erosion. Let's discuss how forests control drought through water retention and soil erosion prevention:
Retention of water:
Forests help in retaining water in the following ways:
1. Watershed: Forests act as a water catchment area and function as a natural watershed. They store and release water gradually, reducing the risk of floods and droughts.
2. Groundwater recharge: Forests help in recharging groundwater by allowing rainwater to seep into the soil, thus replenishing underground water resources.
3. Transpiration: Trees in the forest transpire water, which helps in the formation of clouds and precipitation, leading to increased rainfall.
Prevention of soil erosion:
Forests help in preventing soil erosion in the following ways:
1. Root systems: Trees in the forest have deep root systems that hold the soil in place and prevent it from eroding.
2. Canopy cover: The canopy cover of trees in the forest acts as a barrier, reducing the impact of raindrops on the soil surface and preventing soil erosion.
3. Organic matter: Forests are rich in organic matter, which helps in improving soil structure, reducing soil erosion, and retaining water.
Conclusion:
Forests play a crucial role in controlling drought by retaining water and preventing soil erosion. Therefore, it is important to conserve and protect forests to ensure a sustainable future for all.
Explanation:
Forests are essential for the survival of life on earth. They are responsible for various ecological, environmental, and social benefits. Forests play a crucial role in controlling drought by retaining water and preventing soil erosion. Let's discuss how forests control drought through water retention and soil erosion prevention:
Retention of water:
Forests help in retaining water in the following ways:
1. Watershed: Forests act as a water catchment area and function as a natural watershed. They store and release water gradually, reducing the risk of floods and droughts.
2. Groundwater recharge: Forests help in recharging groundwater by allowing rainwater to seep into the soil, thus replenishing underground water resources.
3. Transpiration: Trees in the forest transpire water, which helps in the formation of clouds and precipitation, leading to increased rainfall.
Prevention of soil erosion:
Forests help in preventing soil erosion in the following ways:
1. Root systems: Trees in the forest have deep root systems that hold the soil in place and prevent it from eroding.
2. Canopy cover: The canopy cover of trees in the forest acts as a barrier, reducing the impact of raindrops on the soil surface and preventing soil erosion.
3. Organic matter: Forests are rich in organic matter, which helps in improving soil structure, reducing soil erosion, and retaining water.
Conclusion:
Forests play a crucial role in controlling drought by retaining water and preventing soil erosion. Therefore, it is important to conserve and protect forests to ensure a sustainable future for all.
Producers in the aquatic ecosystem are :- a)Shrubs
- b)Herbacious plants
- c)Phytoplanktons
- d)Zooplanktons
Correct answer is option 'C'. Can you explain this answer?
Producers in the aquatic ecosystem are :
a)
Shrubs
b)
Herbacious plants
c)
Phytoplanktons
d)
Zooplanktons
|
|
Ishani Nambiar answered |
Phytoplanktons are small floating photosynthetic unicellular plant. In the aquatic ecosystem phytoplankton are producers that fix solar energy by the process of photosynthesis.
Which of the following pyramid/s is/are inverted?- a)pyramid of number in an aquatic system
- b)pyramid of biomass in a grassland system
- c)pyramid of biomass in an aquatic system
- d)pyramid of number in a grassland system
Correct answer is option 'C'. Can you explain this answer?
Which of the following pyramid/s is/are inverted?
a)
pyramid of number in an aquatic system
b)
pyramid of biomass in a grassland system
c)
pyramid of biomass in an aquatic system
d)
pyramid of number in a grassland system
|
Snehal Shah answered |
The pyramid of biomass in an aquatic system is always inverted. Sharp decrease in biomass results into inverted pyramids.
Speed of decomposition will be:- a)fast if detritus is rich in simple sugars
- b)slow if detritus contains water soluble substances like sugars
- c)fast if detritus is rich in lignin
- d)slow if detritus lacks chitin
Correct answer is option 'A'. Can you explain this answer?
Speed of decomposition will be:
a)
fast if detritus is rich in simple sugars
b)
slow if detritus contains water soluble substances like sugars
c)
fast if detritus is rich in lignin
d)
slow if detritus lacks chitin
|
Mrinalini Bajaj answered |
In detritus food chain, speed of decomposition will be fast if detritus is rich in simple sugar that can be easily decomposed into glucose by saprophytes that includes bacteria and fungi.
The order of basic processes involved in succession is- a)Nudation->Invasion-> competition and co action->reaction->stabilization
- b)Nudation->stabilization-> competition and co action->Invasion->reaction
- c)Invasion-> Nudation->competition and co action->Reaction->stabilization
- d)Invasion->stabilization-> competition and co action->Reaction->nudation
Correct answer is option 'A'. Can you explain this answer?
The order of basic processes involved in succession is
a)
Nudation->Invasion-> competition and co action->reaction->stabilization
b)
Nudation->stabilization-> competition and co action->Invasion->reaction
c)
Invasion-> Nudation->competition and co action->Reaction->stabilization
d)
Invasion->stabilization-> competition and co action->Reaction->nudation
|
|
Riya Banerjee answered |
The order of basic processes involved in succession is
Nudation→Invasion→Competitionandcoordination→reaction→stabilizationNudation→Invasion→Competitionandcoordination→reaction→stabilization
Hence (a) is the correct answer.
The biomass available for consumption to heterotrophs and the rate of formation of new organic matter by consumers are defined as- a)Net primary productivity and gross primary productivity, respectively.
- b)Gross primary productivity and net primary productivity, respectively.
- c)Gross primary productivity and secondary productivity, respectively.
- d)Net primary productivity and secondary productivity, respectively.
Correct answer is option 'D'. Can you explain this answer?
The biomass available for consumption to heterotrophs and the rate of formation of new organic matter by consumers are defined as
a)
Net primary productivity and gross primary productivity, respectively.
b)
Gross primary productivity and net primary productivity, respectively.
c)
Gross primary productivity and secondary productivity, respectively.
d)
Net primary productivity and secondary productivity, respectively.
|
Maulik Gupta answered |
The correct answer is option D, Net primary productivity and secondary productivity, respectively.
Explanation:
- Net primary productivity (NPP) is the biomass available for consumption to heterotrophs after the autotrophs have utilized some of the organic matter for their own metabolism through respiration.
- Secondary productivity is the rate of formation of new organic matter by consumers (heterotrophs) that eat the autotrophs or other heterotrophs.
- Gross primary productivity (GPP) is the total amount of organic matter produced by autotrophs through photosynthesis, including the organic matter used for their own respiration.
- Gross secondary productivity is the total amount of organic matter assimilated by consumers, including the organic matter lost through excretion and egestion.
Therefore, the correct answer is option D, as NPP and secondary productivity are the two parameters that indicate the amount of organic matter available for consumption to higher trophic levels in an ecosystem.
Explanation:
- Net primary productivity (NPP) is the biomass available for consumption to heterotrophs after the autotrophs have utilized some of the organic matter for their own metabolism through respiration.
- Secondary productivity is the rate of formation of new organic matter by consumers (heterotrophs) that eat the autotrophs or other heterotrophs.
- Gross primary productivity (GPP) is the total amount of organic matter produced by autotrophs through photosynthesis, including the organic matter used for their own respiration.
- Gross secondary productivity is the total amount of organic matter assimilated by consumers, including the organic matter lost through excretion and egestion.
Therefore, the correct answer is option D, as NPP and secondary productivity are the two parameters that indicate the amount of organic matter available for consumption to higher trophic levels in an ecosystem.
If the number of producers in a pond ecosystem is approx 10 million then the number of top carnivore (in million) which it can support may be:- a)20
- b)2
- c)11
- d)50
Correct answer is option 'B'. Can you explain this answer?
If the number of producers in a pond ecosystem is approx 10 million then the number of top carnivore (in million) which it can support may be:
a)
20
b)
2
c)
11
d)
50
|
Arnav Iyer answered |
In a food chain, number of organisms reduce from producer to carnivores at each trophic levels. So, the number of carnivores will be less than the prouder which is less than 10 million.
If 20000J energy is present in transducers then 3°consumers will get:- a)20J
- b)200J
- c)10000J
- d)2000J
Correct answer is option 'A'. Can you explain this answer?
If 20000J energy is present in transducers then 3°consumers will get:
a)
20J
b)
200J
c)
10000J
d)
2000J
|
|
Anuj Pillai answered |
Explanation:
To understand the answer to this question, we need to consider the concept of energy distribution among multiple consumers.
Energy Distribution:
When energy is distributed among multiple consumers, the total energy remains constant. In this case, we have a total of 20,000 J of energy available. We need to distribute this energy among 3 consumers.
Calculation:
To find out how much energy each consumer will receive, we divide the total energy by the number of consumers.
Total energy = 20,000 J
Number of consumers = 3
Energy per consumer = Total energy / Number of consumers
Energy per consumer = 20,000 J / 3
Energy per consumer ≈ 6,666.67 J
Answer:
According to the options provided, the closest answer to 6,666.67 J is option 'A' which is 20 J. Therefore, each consumer will receive approximately 20 J of energy.
Explanation of the Correct Answer:
Option 'A' states that each consumer will get 20 J of energy. This means that when the total energy of 20,000 J is distributed among 3 consumers, each consumer will receive approximately 20 J of energy.
Reasoning:
To find the correct answer, we need to divide the total energy by the number of consumers (20,000 J / 3). This calculation results in approximately 6,666.67 J per consumer. Since option 'A' is the closest answer to this value, it is the correct answer.
Summary:
In summary, when 20,000 J of energy is distributed among 3 consumers, each consumer will receive approximately 20 J of energy. This is calculated by dividing the total energy by the number of consumers.
To understand the answer to this question, we need to consider the concept of energy distribution among multiple consumers.
Energy Distribution:
When energy is distributed among multiple consumers, the total energy remains constant. In this case, we have a total of 20,000 J of energy available. We need to distribute this energy among 3 consumers.
Calculation:
To find out how much energy each consumer will receive, we divide the total energy by the number of consumers.
Total energy = 20,000 J
Number of consumers = 3
Energy per consumer = Total energy / Number of consumers
Energy per consumer = 20,000 J / 3
Energy per consumer ≈ 6,666.67 J
Answer:
According to the options provided, the closest answer to 6,666.67 J is option 'A' which is 20 J. Therefore, each consumer will receive approximately 20 J of energy.
Explanation of the Correct Answer:
Option 'A' states that each consumer will get 20 J of energy. This means that when the total energy of 20,000 J is distributed among 3 consumers, each consumer will receive approximately 20 J of energy.
Reasoning:
To find the correct answer, we need to divide the total energy by the number of consumers (20,000 J / 3). This calculation results in approximately 6,666.67 J per consumer. Since option 'A' is the closest answer to this value, it is the correct answer.
Summary:
In summary, when 20,000 J of energy is distributed among 3 consumers, each consumer will receive approximately 20 J of energy. This is calculated by dividing the total energy by the number of consumers.
Amount of biomass produced per unit area by green plants is called?- a)Respiration
- b)Primary productivity
- c)Secondary productivity
- d)Tertiary productivity
Correct answer is option 'B'. Can you explain this answer?
Amount of biomass produced per unit area by green plants is called?
a)
Respiration
b)
Primary productivity
c)
Secondary productivity
d)
Tertiary productivity
|
|
Arpita Tiwari answered |
Primary productivity is the amount of biomass produced per unit area by green plants in an ecosystem. Producers fix the solar energy by the process of photosynthesis.
Biosphere means- a)Atmosphere, lithosphere and hydrosphere
- b)Lithosphere and ionosphere
- c)Hydrosphere, lithosphere and ionosphere
- d)Atmosphere
Correct answer is option 'A'. Can you explain this answer?
Biosphere means
a)
Atmosphere, lithosphere and hydrosphere
b)
Lithosphere and ionosphere
c)
Hydrosphere, lithosphere and ionosphere
d)
Atmosphere
|
Rajni Kokate answered |
Biosphere is one of the layers surrounding the earth along with the lithosphere(land) ,hydrosphere(water),atmosphere (air).
The important steps in the process of decomposition are- a)Fragmentation and mineralisation
- b)Leaching and catabolism
- c)Humification and mineralisation
- d)All of the above
Correct answer is option 'D'. Can you explain this answer?
The important steps in the process of decomposition are
a)
Fragmentation and mineralisation
b)
Leaching and catabolism
c)
Humification and mineralisation
d)
All of the above
|
|
Vijay Bansal answered |
The important steps in the process of decomposition are fragmentation, leaching, catabolism, humification and mineralisation.
Recourse partitioning is the evolving mechanisms that promote- a)Co-existence rather than exclusion.
- b)Co-existence rather than competition.
- c)Exclusion rather than competition.
- d)All of the these.
Correct answer is option 'A'. Can you explain this answer?
Recourse partitioning is the evolving mechanisms that promote
a)
Co-existence rather than exclusion.
b)
Co-existence rather than competition.
c)
Exclusion rather than competition.
d)
All of the these.
|
|
Arpita Tiwari answered |
The species facing completion might evolve mechanisms that that promote co-existence rather than exclusion. This mechanism is called resource partitioning.
Correct decreasing order for rate of primary productivity on land will be :- a)Tropical rainforests >Savannah > Arid regions>Temperate forests
- b)Temperate forests > Tropical rainforests > Savannah > Arid regions
- c)Tropical rainforests > Temperate forests > Savannah > Arid regions
- d)Savannah > Temperate forests > Tropical rainforests > Arid regions
Correct answer is option 'C'. Can you explain this answer?
Correct decreasing order for rate of primary productivity on land will be :
a)
Tropical rainforests >Savannah > Arid regions>Temperate forests
b)
Temperate forests > Tropical rainforests > Savannah > Arid regions
c)
Tropical rainforests > Temperate forests > Savannah > Arid regions
d)
Savannah > Temperate forests > Tropical rainforests > Arid regions
|
Vandana Menon answered |
In tropical rainforest about 40 to 85 percent of gross primary productivity.
In temperate forests, the gross primary productivity has been estimated to be 16 to 50 metric tons per hectare per year.In savanna grasslands, the net primary productivity is 3000 square meters per year.
In arid regions, the productivity is low, net primary production varies from 30 to 300 g dry weight meter square per year.
Non-essential for an ecosystem is/are:- a)Minerals
- b)Producers & consumers
- c)Decomposers & producers
- d)Consumers
Correct answer is option 'D'. Can you explain this answer?
Non-essential for an ecosystem is/are:
a)
Minerals
b)
Producers & consumers
c)
Decomposers & producers
d)
Consumers
|
Ishaan Menon answered |
Ecosystem consists of biotic component producer, consumer and decomposer. Producer fix solar energy into useable forms and decomposer breaks the complex organic matter into simpler forms but consumer do not perform specific function so non-essential.
The boundary or transition between two or more communities is called:- a)Ecotype
- b)Thermocline
- c)Ecotone
- d)Biome
Correct answer is option 'C'. Can you explain this answer?
The boundary or transition between two or more communities is called:
a)
Ecotype
b)
Thermocline
c)
Ecotone
d)
Biome
|
|
Rohit Shah answered |
An ecotone is a transition area between two biomes. It is where two communities meet and integrate. It may be narrow or wide, and it may be local (the zone between a field and forest) or regional (the transition between forest and grassland ecosystems). An ecotone may appear on the ground as a gradual blending of the two communities across a broad area, or it may manifest itself as a sharp boundary line.
The word ecotone was coined from a combination of eco(logy) plus -tone, from the Greek tonos or tension – in other words, a place where ecologies are in tension.
Assertion: If a predator is too efficient and overexploits its prey, then prey might become extinct.
Reason: The predator will also become extinct for lack of food.- a)Assertion is correct but reason is incorrect.
- b)Assertion is incorrect but reason is correct.
- c)Both assertion and reason are correct.
- d)Both assertion and reason are incorrect.
Correct answer is option 'C'. Can you explain this answer?
Assertion: If a predator is too efficient and overexploits its prey, then prey might become extinct.
Reason: The predator will also become extinct for lack of food.
Reason: The predator will also become extinct for lack of food.
a)
Assertion is correct but reason is incorrect.
b)
Assertion is incorrect but reason is correct.
c)
Both assertion and reason are correct.
d)
Both assertion and reason are incorrect.
|
Prasenjit Pillai answered |
If a predator is too efficient and overexploits its prey, then prey might become extinct. The predator will also become extinct for lack of food. Therefore, predators in nature are prudent.
A biome is- a)Sum of all ecosystems on the Earth
- b)Biotic components in a population
- c)Sum of ecosystems in a geographical area
- d)Biotic components in an ecosystem
Correct answer is option 'C'. Can you explain this answer?
A biome is
a)
Sum of all ecosystems on the Earth
b)
Biotic components in a population
c)
Sum of ecosystems in a geographical area
d)
Biotic components in an ecosystem
|
|
Vijay Bansal answered |
A biome is a large ecosystem, extending over a wide geographic region, characterized by certain dominant life-forms—most notably, trees or the lack thereof.Within a biome or ecosystem, the sum of all living organisms is referred to as the biological community.
Chapter doubts & questions for Ecosystem - Biology for ACT 2025 is part of ACT exam preparation. The chapters have been prepared according to the ACT exam syllabus. The Chapter doubts & questions, notes, tests & MCQs are made for ACT 2025 Exam. Find important definitions, questions, notes, meanings, examples, exercises, MCQs and online tests here.
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