Section 2 New Unit A Interactions and Ecosystems Presentation PDF

02 SECTION The Flow of Energy and Cycling of Matter in Ecosystems 2.1 Ecosystems Have Interactions between: Producers Consumers Decomposers Consumers Consumer Consumer is any organism that has to seek out and eat, or consume, other living things for food. According to this definition, you are ce...

02 SECTION The Flow of Energy and Cycling of Matter in Ecosystems 2.1 Ecosystems Have Interactions between: Producers Consumers Decomposers Consumers Consumer Consumer is any organism that has to seek out and eat, or consume, other living things for food. According to this definition, you are certainly a consumer. Carnivore Herbivore Omnivore Example: Wolf Tiger Dog Human Example: Goat Zebra Gorilla Example: Pig Bear Racoon Human Animals like cats, hyenas, seals, and praying mantises, which consume mainly animal food. Animals like moose, elephants, and grasshoppers, which consume mainly plants and plant-like living things Animals like humans, bears, and raccoons, which consume other animals as well as plants. Producers Producer Organisms that produce food for themselves and other organisms. Producers are any kind of green plant. Green plants make their food by taking sunlight and using the energy to make sugar. The plant uses this sugar, also called glucose to make many things, such as wood, leaves, roots, and bark. Photoautotrophs Chemoautotrophs Photoautotrophs use energy from sunlight to make food by photosynthesis. They include plants, algae, and certain bacteria. Chemoautotrophs use energy from chemical compounds to make food by chemosynthesis. They include some bacteria and also archaea. Archaea are microorganisms that resemble bacteria. A convenient way to show how energy moves among living things in an ecosystem. Food Chains Tertiary Consumer (omnivore) Secondary Consumer (carnivore) Primary Consumer (herbivore) Producer In a food chain, the energy flow follows the 10 percent law. According to this law, only 10 percent of energy is transferred from one trophic level to the other. The Process of Photosynthesis Photosynthesis Plants absorb the sun’s energy through their leaves. Inside the leaves, this energy is used to rearrange the particles that make up water and carbon dioxide. Two products result from this rearrangement: food and oxygen. The food is in the form of sugars and starches. These nutrients allow the plant to grow. The oxygen is released back into the air. Plants need two raw materials to make their food. Raw materials are materials in their natural state. The Importance of Photosynthesis 1. Photosynthesis converts the sun’s energy into chemical energy in plants and stores it in the form of sugars and starches. Your body can use this stored energy when you eat plants, plant-based products (e.g., bread), or plant-eating animals. Photosynthesis provides the oxygen in the air you breathe. 2. Photosynthesis provides the oxygen in the air you breathe. Through photosynthesis, plants produce the food and oxygen that all food consumers need to survive. That’s why scientists call plants and plant-like living things producers. Cellular Respiration Cellular Respiration Cellular respiration is a chemical reaction that occurs within the cells of all living things. It combines food and oxygen to produce carbon dioxide, water, and energy. The food is in the form of the sugar glucose. The energy and water are used to carry out life functions. The carbon dioxide is given off (in plants) and exhaled during breathing (in animals). Photosynthesis vs. Cellular Respiration Scavengers and Decomposers Our planet would be littered with dead bodies and waste materials if not for a special group of consumers. These consumers get the matter and energy they need from wastes and dead plants and animals. Scavengers Decomposers Example: Crows Ravens Raccoon Coyote Example: Fungi (mushrooms) Beetles Earthworms Scavengers are consumers that don’t usually kill for their own food. Instead, they feed off the remains of living things that are killed by other consumers. Decomposers are consumers that break down (decompose) dead plants and animals. They also break down animal waste materials. Known as the “clean up crew”. Decomposers Can be Helpful or Harmful Baker’s Yeast The carbon dioxide that baker’s yeast gives off during baking allows bubbles to form and bread and pastries to rise. E. Coli Found in your intestines, this decomposer helps to break down nutrients to be absorbed by the body. The also create vitamins for the body. Vitamin K - to help with blood clotting and building bones. Vitamin B12 - helps produce red blood cells. Candida-Albicans Candida albicans—a kind of yeast found in the moist mucus or mucus-producing areas of your body, such as your throat and mouth. When the body’s immune system is weak, these decomposers can grow and reproduce rapidly. This results in a disease called thrush. E. Coli 0157:H7 E. coli bacteria 0157:H7—a form of E. coli sometimes found in common food products such as ground beef, milk, and apple juice. When these decomposers break down food, they produce highly toxic chemicals that can cause food poisoning. 2.2 Food Chains and the Flow of Energy in Ecosystems Food Chains - Calculating Energy Transfer Tertiary Consumer If the energy in the primary producer (grass) is stated as 4500 Kcal, and the rabbit as the primary consumer received 500 Kcal during energy transfer, what is the % of energy transferred from the consumer to (omnivore) Secondary Consumer (carnivore) Primary Consumer (herbivore) Producer 500 4500 = 11% 2.3 Food Webs Food Webs Food chains is only a simplified illustration of the interaction between producers and consumers. The reality is there are many chains that interact with one another. These are referred to as Food Webs. Food Webs 2.4 Matter Cycles in Ecosystems The Water Cycle Three main processes are responsible for the water cycle: evaporation, condensation, and precipitation. Heat from the sun causes water in bodies such as oceans, rivers, and lakes to evaporate (change from liquid water to water vapour). Water vapour condenses into clouds. It returns to Earth in the form of precipitation (rain, hail, and snow). Fuel-burning factories and motor vehicles add water vapour (steam) to the atmosphere. People and other animals drink water. They give off water vapour into the atmosphere whenever they exhale or perspire. Plants take in water from the soil through their roots. They give off water vapour. The Carbon Cycle The carbon substances may, over millions of years, change to become fuels such as coal, oil, and natural gas. Animals use oxygen in combination with food to release the energy they need to survive. (This is called cellular respiration.) This process gives off carbon dioxide as a by-product. Animals on land add carbon dioxide mainly to air. Animals in bodies of water add carbon dioxide mainly to water. Plants take in carbon dioxide from the atmosphere and water from the soil. Photosynthesis transforms these substances into food and oxygen. Fuel-burning factories and motor vehicles add carbon dioxide to the atmosphere. Decomposers add other forms of carbon to the soil and to water. SECTION 2 QUIZ