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Pyramid of numbers in a grassland/true ecosystem is
Pyramid of numbers in a g rassland ecosystem is always upright. For most ecosystem, like grass and ecosystem. Pyramids of numbers are upright because numbering of organisms decrease at successively higher trophic levels. Trophic level refers to the organisms, position in the food chain.
Food chain in which micro - organisms breakdown the food formed by primary producers is
Detritus food chain being with dead organic matter with dead plant parts, animals and their excretory product which is being acted upon by decomposers such as saprophytes to obtain energy needed for their survival.
Pick up the correct food chain
Phytoplankton → zooplankton → Fish. This is a type of food chain in aquatic ecosystem.
Pedology is science of
Soil is the uppermost weathered layer or earth's crust and is composed of minerals and partly decomposed organic matter. Pedologist is a scientist who studies origin, composition and distribution of soil and the materials from which the soil is made.
River water deposits
River water deposits alluvial soil. Alluvial soil- formed by the alluvium deposition by the rivers when they slowly lose their carrying capacity due to decrease in velocity. These consist of diverse ratio of sand, silt and clay. These the most widespread soil in India the entire northern plains as loamy soil. It contains roughly equal amount of sand silt and clay. It is more fertile than sandy soil.
Laterite soil-formed and hot wet tropical areas are formed by intensive and long lasting weathering of underlying rocks and are rich in iron and aluminium.
Study of inter-relationships between organisms and their environment is
German biologist Ernst Haeckel coined the term 'ecology', the study of interrelationship between organisms and their environment. Ecosystem, consist of different communities of organism and the physical environment with which they interact. Phytogeography is the study of geographic distribution of plants species on earth.
Pyramid of numbers deals with number of
Pyramid of number represents the number of individuals on each tropic level.
Pyramid of numbers in a pond ecosystem is
The correct option is Option C.
Pyramid of number in a pond ecosystem is always upright, showing the number of individual organisms at each level. This number then shows a decrease towards apex, primary consumers are lesser in number than the grasses; the secondary consumers are lesser in number than the primary consumers.
The pyramid which cannot be inverted in a stable ecosystem is that of
Energ y pyramid can not be inver ted because energy always flows in one direction only. According to 10% law of energy transfer given by Lindemann (1972), during transfer of energy from one trophic level to other there is always loss in respiration and other activities only 10% of energy is transfered to neat trophic level. So the amount of energy flow decreases with successive trophic levels.
In grass-deer-tiger food chain, grass biomass is one tonne. The tiger biomass shall be
According to 10% law of Lindemann,if 1 tonne (1000kg) biomass is present in the grass, only 10% of it means 100 kg will go into deer and in tiger, the biomass will be only 10kg, i.g. 10% of deer' biomass.
In a biotic community, the most important factor for survival of an animal is
An ecosystem is made up of biotic and abiotic factors. Biotic factors involves animals, plants, microorganisms. Abiotic factors involves temperature, air, water, land. Biotic community involves group of interacting populations. In a biotic community, the most important factor for survival of an animal is predators. They control the size of prey populations. They also increases the biodiversity by preventing a single species for being dominant.
Thus, the correct answer is 'Predators.'
Second most important trophic level in a lake is
First tropic level in a lake is phytoplankton, second is zooplankton.
Bulk CO2 fixation occurs in
Due to majority of phytoplanktons.
Desert plants are generally
Succulent plants are fleshy xerophytes, which can grow in low water level area (desert). That is why, they are called as desert plants.
Which of the following does not have stomata?
In submerged hydrophytes whole plant body remains under water. e.g.
Ceratophyllum and Utricularia. In these plants, stomata is absent and gaseous exchange takes place through general body surface.
If we completely remove the decomposers from an ecosystem, its functioning will be adversely affected, because
The decomposers act on the dead organic matter and break them down into simpler compounds and minerals.
The primary succession refers to the development of communities on a
The primary succession means the development of communities only on a newly exposed habitat with no record of earlier vegetation.
Which of the following is the most stable ecosystem?
The oceans cover about 2/3 of the whole surface of our earth. Thus it is the most stable ecosystem, because of buffering action by water.
In a biotic community, the primary consumers are
In a biotic community the herbivores (goat, deer) are those animals, which consume the primary producers (green plants). Hence they are primary consumers.
Which of the following pairs is a sedimentary type of biogeochemical cycle?
Biogeochemical cycles : Two types :
(a) Gaseous : Biogenetic materials involved in circulation are gases eg. N2, O2, CO2 etc.
(b) Sedimentary : Biogenetic materials involved in circulation are non-gaseous eg. P2, Ca, S etc. forms rocks.
Flamingoes breed in
Flamingoes breed in chilka lake.
In a food chain, the largest population is that of
Producers are the direct and indirect source of food for all the trophic levels. They are always more in number.
The transfer of energ y from one trophic level to another is governed by the 2nd law of thermodynamics. The average efficiency of energy transfer from herbivores to carnivores is
According to the 10% law, at each trophic level, only 10% of the energy received is transfered to the next trophic level.
Niche of a species in an ecosystem refers to its
Niche is a specific part of the habitat that is determined by the functioning of the population like shelter, type of food, season etc.
Which of the following ecosystems has highest rate of gross primary production?
The Gross primary productivity of an ecosystem is the total amount of organic matter produced by its producers, i.e. autotrophs. Coral reefs have maximum and deserts have the lowest productivity.