Energy Flow Through an Ecosystem

Transcription

1 Energy Flow Through an Ecosystem Food Chains, Food Webs, Energy Pyramids 1 Ecosystems An ecosystem is all of the organisms living in an area together with their physical environment. Ex. An oak forest, a coral reef, or even a vacant lot is an ecosystem 2 Energy Flow: Depends on the organism Begins with the SUN Photosynthesis 6CO 2 + 6H 2 O + sunlight & chlorophyll àc 6 H 12 O 6 + 6O 2 3 1

2 Photosynthesis Chemical reaction where green plants, algae and bacteria use water & carbon dioxide to store the sun s energy in glucose ENERGY is stored in glucose Glucose is stored as starch in plants 4 Carbohydrates Carbohydrates are energy-rich molecules which organisms use to carry out daily activities 5 Organisms that can make glucose during photosynthesis are called PRODUCERS. 6 2

3 Producers use most of the energy they make for themselves. They are self-feeders, AKA autotrophs! 7 Producers use cellular respiration to supply the energy they need to live. 8 The energy that is not used by producers can be passed on to organisms that cannot make their own energy. 9 3

4 Organisms that cannot make their own energy are called CONSUMERS. 10 Consumers that eat producers to get energy: Are first order (1 st ) or primary consumers Are herbivores (planteaters) 11 Most of the energy the primary consumer gets from the producer is used by the consumer. 12 4

5 Some of the energy moves into the atmosphere as heat. 13 Some energy in the primary consumer is STORED & not lost to the atmosphere or used by the consumer itself. This energy is available for another consumer (predator). 14 A Consumer that Eats Another Consumer for Energy: Is called a secondary or 2nd order consumer May be a carnivore or an omnivore May be a predator May be a scavenger 15 5

6 Most of the energy the secondary consumer gets from the primary consumer is used by the secondary consumer. 16 Some of the energy is lost as heat, but some energy is stored and can passed on to another consumer. 17 A consumer that eats a consumer that already ate a consumer: Is called a 3rd order or tertiary consumer May be a carnivore or an omnivore May be a predator May be a scavenger 18 6

7 Carnivores are those that feed on flesh or are meat-eaters. Ex. lions, hawks, snakes, spiders, sharks, alligators, and whales 19 Consumers that hunt & kill other consumers are called predators. The animals that are hunted & killed are called prey. 20 Consumers that eat producers & other consumers Are called omnivores Omnivores eat plants and animals Ex. - Bears, pigs, gorillas, rats, raccoons, cockroaches, humans, chickens, lizards, turtles 21 7

8 Consumers that eat other dead consumers are called scavengers Ex. - hyenas, jackals, opossums, vultures, crows, crabs, lobsters and cockroaches 22 Consumers that get their food by breaking down dead organisms are called decomposers. Ex. bacteria and fungi 23 6O 2 + C 6 H 12 O 6 --> 6H 2 O + 6CO 2 + energy CELLULAR RESPIRATION is the chemical reaction that releases the energy in glucose. 24 8

9 6O 2 + C 6 H 12 O 6 --> 6H 2 O + 6CO 2 + energy It is different from breathing! is the reverse of photosynthesis is used by all living things! Uses sugar and oxygen to make CO 2, H 2 O, and NRG 25 The transfer of energy from the sun to producer to primary consumer then to higher order consumers can be shown in a FOOD CHAIN. 26 Food Chains Show Available Energy A sequence in which energy is transferred from one organism to the next as each organism eats another organism 27 9

10 More Food Chains 28 Food Webs: Food webs are interconnected food chains that show the feeding relationships in an ecosystem 29 Another way of showing the transfer of energy in an ecosystem is the ENERGY PYRAMID 30 10

11 Energy Pyramids Show Amount of available energy decreases for higher consumers It takes a large number of producers to support a small number of primary consumers It takes a large number of primary consumers to support a small number of secondary consumers Each step in the transfer of energy is known as a trophic level How Many Chains are in this web? 33 11

12 Identify the Producers, Consumers, & Decomposers: Count the Food Chains! 34 12