Food Chains Webs https www youtube comwatch v0

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Food Chains & Webs https: //www. youtube. com/watch? v=0 ZOvq Yyp. Ouo (c) Mc.

Food Chains & Webs https: //www. youtube. com/watch? v=0 ZOvq Yyp. Ouo (c) Mc. Graw Hill Ryerson 2007

Energy Flow in Nature • An organism is a living thing. w Includes: Plants,

Energy Flow in Nature • An organism is a living thing. w Includes: Plants, animals, micro-organisms, fungi, insects • An organism: 1. Obtains energy from the environment 2. Contributes energy to the environment • Plants are called “producers” because they produce carbohydrates from carbon dioxide, water and the sun’s energy (in photosynthesis). w E. g. , flower • “Consumers” get their energy by feeding on producers or other consumers. w E. g. , bee (feeds on flower) • Decomposition (or biodegradation) is the break-down of wastes and dead organisms. It is done by organisms called See pages 56 - 59 “decomposers” or “detrivores. ”

Food Chains • Different methods are used to represent energy moving through ecosystems: Examples

Food Chains • Different methods are used to represent energy moving through ecosystems: Examples of terrestrial and aquatic food chains 1. Food chains 2. Food webs 3. Food pyramids (next class) • Food chains show the flow of energy in an ecosystem w Each step is a trophic level w Producers = 1 st trophic level w Primary consumers = 2 nd trophic level w Secondary consumers = 3 rd trophic level w Tertiary consumers = 4 th trophic level See pages 59 - 60 w Top level = Top consumers or Top carnivores

Food Chains (continued) • Consumers in a food chain can be classified as: 1.

Food Chains (continued) • Consumers in a food chain can be classified as: 1. Detrivores - consumers that obtain energy and nutrients from dead organisms and waste matter w Includes small insects, earthworms, fungi w Detrivores feed at every trophic level w Detrivores have their own, separate food chains, and are very numerous This dung beetle is a detrivore. See page 61

Food Chains (continued) 1. Detrivores 2. Herbivores - primary consumers w herbivores eat plants

Food Chains (continued) 1. Detrivores 2. Herbivores - primary consumers w herbivores eat plants (producers) only 3. Carnivores - secondary or tertiary consumers w Secondary consumers herbivores w Tertiary consumers eat secondary consumers 4. Omnivores - consumers that eat both plants and animals w Examples include humans and bears

 • Which is it: herbivore, carnivore or omnivore? Venus Fly Trap? http: //www.

• Which is it: herbivore, carnivore or omnivore? Venus Fly Trap? http: //www. discovery. com/tv-shows/life/videos/venus-flytrap-catches-flies/

Food Webs • Most organisms are part of many food chains. w Food webs

Food Webs • Most organisms are part of many food chains. w Food webs represent many interconnected food chains. w Arrows represent the direction that energy flows. w Following the arrows leads to the top carnivore(s). See page 62 This food web represents a terrestrial ecosystem that could be found in British Columbia.

FOOD WEBS • https: //www. youtube. com/watch? v=MGODmy. Xkk. PU (c) Mc. Graw Hill

FOOD WEBS • https: //www. youtube. com/watch? v=MGODmy. Xkk. PU (c) Mc. Graw Hill Ryerson 2007

 • Biomass is the total mass of all living things in a given

• Biomass is the total mass of all living things in a given area. (c) Mc. Graw Hill Ryerson 2007