The second law of thermodynamics states that whenever energy is transformed, there is a loss energy through the release of heat. This occurs when energy is transferred between trophic levels as illustrated in a food web. When one animal feeds off another, there is a loss of heat (energy) in the process. Additional loss of energy occurs during respiration and movement. Hence, more and more energy is lost as one moves up through trophic levels. If this pyramid is inverterved, it would violate the law of thermodynamics. Hence the pyramid can never be inverted.

Odum is the father of modern ecology. Clements proposed the theory of plant succession. The tern ecosystem was proposed by Tansley. Elton proposed the concept of ecological pyramids. Hence, it is also called as Eltonian pyramids. Ecological pyramid is a graphical representation that shows the biomass at each trophic level. 

Pyramid of energy represents the amount of energy at different trophic level. It is always upright in shape. Only 10% of energy is transferred from one trophic level to next trophic level. The majority of energy is lost during the transfer of energy. The base of pyramid of energy is always broad indicating maximum amount of energy at the first trophic level. 

In an aquatic ecosystem, the producers are the algae and the phytoplanktons. The primary consumers are the zooplanktons and the next consumers are the fishes. The biomass of the phytoplanktons is less than the zooplanktons. There is increase in the number of the organisms with increasing trophic level. 

Pyramid of energy is ecological pyramid that gives graphic representation of amount of energy trapped by different trophic levels per unit area. It is always upright because during transfer of energy from one trophic level to the next a lot of wastage occurs in feeding, digestion, assimilation and respiration i.e metabolism at each trophic level. Hence, organisms of each trophic level have more energy than each succeeding trophic level and less energy than organisms at previous trophic level. Thus, the correct answer is option D.

Pyramid of energy is ecological pyramid, that represents the flow of energy from one trophic level to the next a lot of wastage occurs in metabolism and energy transfer. Maximum energy content is present in producers and least at top carnivore levels. Thus, the correct answer is option B.

Flow of energy declines as it passes from lower to higher trophic level. The energy decreases from one trophic level to the next trophic level because energy is lost as metabolic heat during transfer of energy. Hence, the pyramid of energy is always upright in any ecosystem and it cannot be inverted in a stable ecosystem. When food energy passes from producers to herbivores to carnivores, only 10% of energy is transferred from one trophic level to another trophic level.

An ecological pyramid is a graphical representation showing relationships between organisms at different trophic level in an ecosystem. Pyramid of biomass is the graphical representation of total amount of living material at each trophic level of a food chain. Pyramid of numbers represent the number of individuals in each trophic level of a food chain. Pyramid of energy represents the amount of energy at each trophic level of a food chain. The ecological pyramid are either upright, inverted or spindle shaped.

An ecological pyramid is a graphic representation of the relationship between organisms at various trophic levels in a food chain. Ecological pyramids are of 3 types, namely biomass, energy and number. Pyramid of Number represents the number of organisms at different trophic levels of food chain. Pyramid of biomass represents the biomass of organisms at different trophic levels of the food chain. Pyramid of energy represents the amount of energy at different trophic levels.

Pyramid of energy represents the amount of energy at each trophic level. In any ecosystem, flow of energy declines as it passes from lower to higher trophic level. This is explained by second law of thermodynamics. Hence, the pyramid of energy always has an upright or steeper vertical gradient. In this, the energy decreases from one trophic level to the next trophic level because energy is lost as metabolic heat during transfer of energy. When food energy passes from producers to herbivores to carnivores, only 10% of energy is transferred from one trophic level to another trophic level.

Pyramid of energy represents the amount of energy at each trophic level. In any ecosystem, flow of energy declines as it passes from lower to higher trophic level. Hence, pyramid of energy is always upright indicating that herbivores have a better energy conversion efficiency than carnivores.  Each successive trophic level has less total energy. In this, the energy decreases from one trophic level to the next trophic level because energy is lost as metabolic heat during transfer of energy. When food energy passes from producers to herbivores to carnivores, only 10% of energy is transferred from one trophic level to another trophic level.

The species that invade a bare area are called pioneer species. In primary succession on rocks, the pioneer species were lichens. The entire sequence of communities that successively change in a given area called sere. The individual transitional community is called seral stage. Pyramid of energy is always upright. Only 10% of energy is transferred from one trophic level to successive trophic level in a pyramid. Pyramid of numbers in a tree ecosystem can be inverted. In this, the first trophic level contains minimum number of individuals and top trophic level contains maximum number of individuals.

In a food chain, only 10% of energy is transferred from one trophic level to another trophic level. If the energy produced at the producer level is 1000 J, then the energy available at the primary consumer level will be 100 J and energy available at the secondary consumer level will be 10 J.

Flow of energy declines as it passes from lower to higher trophic level. This is explained by second law of thermodynamics. According to this law, the energy decreases from one trophic level to the next trophic level because energy is lost as metabolic heat during transfer of energy. When food energy passes from producers to herbivores to carnivores, only 10% of energy is transferred from one trophic level to another trophic level. Hence, the pyramid of energy is always upright.

Correct answer-(D)

An energy pyramid is the graphical representation of energy flow in a particular community. The different trophic levels represent a different group of animals. Here only ten percent of the energy is passed on to the next trophic level. As the organism of one trophic level is consumed by the organism of the next trophic level, energy decreases as it goes up the trophic level. So, the correct answer is "eating grain-fed beef is an inefficient means of obtaining the energy trapped by photosynthesis".

An energy pyramid is a graphical representation designed to show the biomass or bio productivity at each trophic level in a given ecosystem. An energy pyramid is always upright because when energy flows from a particular trophic level, some energy is lost as heat at each step. Thus, the total amount of energy available for utilisation in the top levels is always less than the energy available in the lower levels. Therefore in the pyramid of energy in which each bar indicates the amount of energy present at each trophic level in a given time

Pyramid of energy is always upright and can never be inverted, because when energy flows from a trophic level to the next trophic level some energy is always lost as heat at each step. 

The flow of energy is always unidirectional. The energy passes from primary producers to primary consumers. From primary consumer the energy passed to secondary consumers and then to teritary consumers. Thus the energy pyramid is always upright.

When energy is passed in an ecosystem from one trophic level to the next, only ten percent (10%) of the energy will be passed on. We can consider a typical food chain in the environment. It can be written as follows. Sun -----> Green Plants -----> Insects -----> Frogs -----> Snakes. The sun provides the energy that is used by the green plants. The green plants are the primary producers for the food chain. The energy from the sun is converted by the plants into food. The insects are the primary consumers. They are the first animals to eat the plants. When they eat the plants and obtain some of the energy (10%) they stored when making food. The rest of the energy is lost and dissipated as heat. Insects are eaten by frogs. The frogs are the secondary consumers in this food chain. They obtain part of the energy stored by the insects. The remaining energy stored by the insects is lost. Thus, the correct answer is option C.