Which Organisms are Secondary Consumers in This Food Web

KEY Food Webs and Nutrients Name - ________KEY_______ 1.) Why is sunlight essential to most food chains and food webs? Sunlight is essential to most food webs and chains because the sun is the source of all the energy for that food web or chain. Without the sunlight the entire chain would collapse. 2.) Consider the food chain shown below. Grass
Insects
Frog
Snake a.) How would a decline in the number of frogs affect each of the other organisms in this food chain? If the frogs in the food chain were killed off the insect population that the frogs fed on would increase as they now have lost a predator. The snake population that fed on the frogs would decrease as they lost a food source and lastly the grass the insects fed on would decrease as the insect population increases and feeds on the grass more. b.) Redraw this food chain with the addition of bacteria, in order to show the role of decomposers in this community. grass
insect
frog
snake
decomposer 3a.) What type of food is eaten by a consumer in the second trophic level? Examples of food eaten by a consumer in the second trophic level are producers like grass, leaves and shoots. b.) What type of food is eaten by a consumer in the third trophic level? Examples of food eaten by a consumer in the third trophic level are herbivores like some insects, cows and deer. 4.) Is it possible for an organism to belong to more than one trophic level? Explain using an example. Yes, it is possible for one organism to occupy more than one trophic level. An example would be herring (bird) eating both marsh grass and insects. When the herring eats the marsh grass it is in the second trophic level. When the herring eats the insect it is in the third trophic level. 1 KEY 5.) Us the food web shown below to answer the following questions: killer whale red-tailed hawk rat snail vole bald eagle harbor seal herring salmon grasshopper mosquito marsh vegetation – includes grasses, algae, etc. a.) Which organisms are the top carnivores in the food web? The top carnivores in the food web from the worksheet are the red-tailed hawk, bald eagle, orca and the harbor seal. b.) Which organisms are the producers in this food web? The producers in this food web are the marsh grasses and the algae. c.) If the population of grasshoppers was eliminated from the area, what organisms would lose one of their food sources and why? If grasshoppers died out both the herring and the salmon would lose a food source. d.) Which of the organisms would be classified as primary consumers and which would be classified as secondary consumers? Mosquito’s, snails, voles and grasshoppers would all be primary consumers in this food web. Harbor seals, snow geese, salmon, herring and rats are all secondary consumers in this food web. 6.) Explain the difference between organic and inorganic compounds and give an example of both. The difference between organic and inorganic compounds are that organic must contain carbon with hydrogen and often also include oxygen. Organic compounds also come from living organisms. Inorganic do not contain carbon, hydrogen and usually oxygen all together and don’t usually come from living organisms. Organic examples could be carbohydrates and lipids and inorganic could be salts and water. 2 KEY 7.) Which of the following elements are contained in carbohydrates? 1 Carbon 2 Oxygen 3 Hydrogen 4 nitrogen a.) 1 b.) 1,2 c.) 1, 2, 3 d.) 1, 2, 4 4.) Identify the following compounds as organic or inorganic: a.) NaCl ____inorganic____ b.) C6H12O6 ____ organic ____ c.) CH4 ____ organic ____ d.) NH3 _____ inorganic ____ 10.) Complete the following: a.) carbon dioxide + water
carbohydrate + __oxygen gas__ b.) C6H12O6 + O2
__carbon dioxide gas__ + water c.) The chemical reaction in (a.) is called ____photosynthesis___. d.) The chemical reaction in (b.) is called ____cellular respiration____. 3