18. (a)From the following group of organisms create a food chain which isthe most advantageous for Human beings in terms of energy.RatI Hawk, Rat, Cereal plant,y Goat, Snake, Human Being(b)State the possible disadvantage if the cereal plant is growing in soilrich in pesticides.Construct a food web using the organisms mentioned above.(c)
Answers
A food chain is a linear network of links in a food web starting from producer organisms and ending at apex predator species, detritivores, or decomposer species. eg. Next come organisms that eat the autotrophs; these organisms are called herbivores or primary consumers -- an example is a rabbit that eats grassThe order is the number of steps it takes for that one organism just eaten to get to the bottom of the chain. Generally plants are first order, herbivores second order because they eat plants, omnivores and carnivores at least second order.1)Trophic level T1 has maximum number of organisms. Because they are the original source of energy. 2)In trophic level T4, chemicals like DDT are accumulated in highest concentration. As these chemicals are not biodegradable they get accumulated progressively at each trophic levelLevel 2: Animals that eat plants or herbivores (primary consumers) Level 3: Animals that eat herbivores (secondary consumers, carnivores) Level 4: Animals that eat carnivores (tertiary consumers, carnivores) Level 5: Animals at the top of the food chain are called apex predators.The 10% Rule means that when energy is passed in an ecosystem from one trophic level to the next, only ten percent of the energy will be passed on. A trophic level is the position of an organism in a food chain or energy pyramid. food chains and webs have at least two or three trophic levels. Generally, there are a maximum of four trophic levels. Many consumers feed at more than one trophic level. Humans, for example, are primary consumers when they eat plants such as vegetables.